1/* SPDX-License-Identifier: GPL-2.0 */ 2/* 3 * arch/ia64/kernel/entry.S 4 * 5 * Kernel entry points. 6 * 7 * Copyright (C) 1998-2003, 2005 Hewlett-Packard Co 8 * David Mosberger-Tang <davidm@hpl.hp.com> 9 * Copyright (C) 1999, 2002-2003 10 * Asit Mallick <Asit.K.Mallick@intel.com> 11 * Don Dugger <Don.Dugger@intel.com> 12 * Suresh Siddha <suresh.b.siddha@intel.com> 13 * Fenghua Yu <fenghua.yu@intel.com> 14 * Copyright (C) 1999 VA Linux Systems 15 * Copyright (C) 1999 Walt Drummond <drummond@valinux.com> 16 */ 17/* 18 * ia64_switch_to now places correct virtual mapping in in TR2 for 19 * kernel stack. This allows us to handle interrupts without changing 20 * to physical mode. 21 * 22 * Jonathan Nicklin <nicklin@missioncriticallinux.com> 23 * Patrick O'Rourke <orourke@missioncriticallinux.com> 24 * 11/07/2000 25 */ 26/* 27 * Copyright (c) 2008 Isaku Yamahata <yamahata at valinux co jp> 28 * VA Linux Systems Japan K.K. 29 * pv_ops. 30 */ 31/* 32 * Global (preserved) predicate usage on syscall entry/exit path: 33 * 34 * pKStk: See entry.h. 35 * pUStk: See entry.h. 36 * pSys: See entry.h. 37 * pNonSys: !pSys 38 */ 39 40 41#include <linux/pgtable.h> 42#include <asm/asmmacro.h> 43#include <asm/cache.h> 44#include <asm/errno.h> 45#include <asm/kregs.h> 46#include <asm/asm-offsets.h> 47#include <asm/percpu.h> 48#include <asm/processor.h> 49#include <asm/thread_info.h> 50#include <asm/unistd.h> 51#include <asm/ftrace.h> 52#include <asm/export.h> 53 54#include "minstate.h" 55 56 /* 57 * execve() is special because in case of success, we need to 58 * setup a null register window frame. 59 */ 60ENTRY(ia64_execve) 61 /* 62 * Allocate 8 input registers since ptrace() may clobber them 63 */ 64 .prologue ASM_UNW_PRLG_RP|ASM_UNW_PRLG_PFS, ASM_UNW_PRLG_GRSAVE(8) 65 alloc loc1=ar.pfs,8,2,3,0 66 mov loc0=rp 67 .body 68 mov out0=in0 // filename 69 ;; // stop bit between alloc and call 70 mov out1=in1 // argv 71 mov out2=in2 // envp 72 br.call.sptk.many rp=sys_execve 73.ret0: 74 cmp4.ge p6,p7=r8,r0 75 mov ar.pfs=loc1 // restore ar.pfs 76 sxt4 r8=r8 // return 64-bit result 77 ;; 78 stf.spill [sp]=f0 79 mov rp=loc0 80(p6) mov ar.pfs=r0 // clear ar.pfs on success 81(p7) br.ret.sptk.many rp 82 83 /* 84 * In theory, we'd have to zap this state only to prevent leaking of 85 * security sensitive state (e.g., if current->mm->dumpable is zero). However, 86 * this executes in less than 20 cycles even on Itanium, so it's not worth 87 * optimizing for...). 88 */ 89 mov ar.unat=0; mov ar.lc=0 90 mov r4=0; mov f2=f0; mov b1=r0 91 mov r5=0; mov f3=f0; mov b2=r0 92 mov r6=0; mov f4=f0; mov b3=r0 93 mov r7=0; mov f5=f0; mov b4=r0 94 ldf.fill f12=[sp]; mov f13=f0; mov b5=r0 95 ldf.fill f14=[sp]; ldf.fill f15=[sp]; mov f16=f0 96 ldf.fill f17=[sp]; ldf.fill f18=[sp]; mov f19=f0 97 ldf.fill f20=[sp]; ldf.fill f21=[sp]; mov f22=f0 98 ldf.fill f23=[sp]; ldf.fill f24=[sp]; mov f25=f0 99 ldf.fill f26=[sp]; ldf.fill f27=[sp]; mov f28=f0 100 ldf.fill f29=[sp]; ldf.fill f30=[sp]; mov f31=f0 101 br.ret.sptk.many rp 102END(ia64_execve) 103 104/* 105 * sys_clone2(u64 flags, u64 ustack_base, u64 ustack_size, u64 parent_tidptr, u64 child_tidptr, 106 * u64 tls) 107 */ 108GLOBAL_ENTRY(sys_clone2) 109 /* 110 * Allocate 8 input registers since ptrace() may clobber them 111 */ 112 .prologue ASM_UNW_PRLG_RP|ASM_UNW_PRLG_PFS, ASM_UNW_PRLG_GRSAVE(8) 113 alloc r16=ar.pfs,8,2,6,0 114 DO_SAVE_SWITCH_STACK 115 adds r2=PT(R16)+IA64_SWITCH_STACK_SIZE+16,sp 116 mov loc0=rp 117 mov loc1=r16 // save ar.pfs across do_fork 118 .body 119 mov out1=in1 120 mov out2=in2 121 tbit.nz p6,p0=in0,CLONE_SETTLS_BIT 122 mov out3=in3 // parent_tidptr: valid only w/CLONE_PARENT_SETTID 123 ;; 124(p6) st8 [r2]=in5 // store TLS in r16 for copy_thread() 125 mov out4=in4 // child_tidptr: valid only w/CLONE_CHILD_SETTID or CLONE_CHILD_CLEARTID 126 mov out0=in0 // out0 = clone_flags 127 br.call.sptk.many rp=do_fork 128.ret1: .restore sp 129 adds sp=IA64_SWITCH_STACK_SIZE,sp // pop the switch stack 130 mov ar.pfs=loc1 131 mov rp=loc0 132 br.ret.sptk.many rp 133END(sys_clone2) 134 135/* 136 * sys_clone(u64 flags, u64 ustack_base, u64 parent_tidptr, u64 child_tidptr, u64 tls) 137 * Deprecated. Use sys_clone2() instead. 138 */ 139GLOBAL_ENTRY(sys_clone) 140 /* 141 * Allocate 8 input registers since ptrace() may clobber them 142 */ 143 .prologue ASM_UNW_PRLG_RP|ASM_UNW_PRLG_PFS, ASM_UNW_PRLG_GRSAVE(8) 144 alloc r16=ar.pfs,8,2,6,0 145 DO_SAVE_SWITCH_STACK 146 adds r2=PT(R16)+IA64_SWITCH_STACK_SIZE+16,sp 147 mov loc0=rp 148 mov loc1=r16 // save ar.pfs across do_fork 149 .body 150 mov out1=in1 151 mov out2=16 // stacksize (compensates for 16-byte scratch area) 152 tbit.nz p6,p0=in0,CLONE_SETTLS_BIT 153 mov out3=in2 // parent_tidptr: valid only w/CLONE_PARENT_SETTID 154 ;; 155(p6) st8 [r2]=in4 // store TLS in r13 (tp) 156 mov out4=in3 // child_tidptr: valid only w/CLONE_CHILD_SETTID or CLONE_CHILD_CLEARTID 157 mov out0=in0 // out0 = clone_flags 158 br.call.sptk.many rp=do_fork 159.ret2: .restore sp 160 adds sp=IA64_SWITCH_STACK_SIZE,sp // pop the switch stack 161 mov ar.pfs=loc1 162 mov rp=loc0 163 br.ret.sptk.many rp 164END(sys_clone) 165 166/* 167 * prev_task <- ia64_switch_to(struct task_struct *next) 168 * With Ingo's new scheduler, interrupts are disabled when this routine gets 169 * called. The code starting at .map relies on this. The rest of the code 170 * doesn't care about the interrupt masking status. 171 */ 172GLOBAL_ENTRY(ia64_switch_to) 173 .prologue 174 alloc r16=ar.pfs,1,0,0,0 175 DO_SAVE_SWITCH_STACK 176 .body 177 178 adds r22=IA64_TASK_THREAD_KSP_OFFSET,r13 179 movl r25=init_task 180 mov r27=IA64_KR(CURRENT_STACK) 181 adds r21=IA64_TASK_THREAD_KSP_OFFSET,in0 182 dep r20=0,in0,61,3 // physical address of "next" 183 ;; 184 st8 [r22]=sp // save kernel stack pointer of old task 185 shr.u r26=r20,IA64_GRANULE_SHIFT 186 cmp.eq p7,p6=r25,in0 187 ;; 188 /* 189 * If we've already mapped this task's page, we can skip doing it again. 190 */ 191(p6) cmp.eq p7,p6=r26,r27 192(p6) br.cond.dpnt .map 193 ;; 194.done: 195 ld8 sp=[r21] // load kernel stack pointer of new task 196 MOV_TO_KR(CURRENT, in0, r8, r9) // update "current" application register 197 mov r8=r13 // return pointer to previously running task 198 mov r13=in0 // set "current" pointer 199 ;; 200 DO_LOAD_SWITCH_STACK 201 202#ifdef CONFIG_SMP 203 sync.i // ensure "fc"s done by this CPU are visible on other CPUs 204#endif 205 br.ret.sptk.many rp // boogie on out in new context 206 207.map: 208 RSM_PSR_IC(r25) // interrupts (psr.i) are already disabled here 209 movl r25=PAGE_KERNEL 210 ;; 211 srlz.d 212 or r23=r25,r20 // construct PA | page properties 213 mov r25=IA64_GRANULE_SHIFT<<2 214 ;; 215 MOV_TO_ITIR(p0, r25, r8) 216 MOV_TO_IFA(in0, r8) // VA of next task... 217 ;; 218 mov r25=IA64_TR_CURRENT_STACK 219 MOV_TO_KR(CURRENT_STACK, r26, r8, r9) // remember last page we mapped... 220 ;; 221 itr.d dtr[r25]=r23 // wire in new mapping... 222 SSM_PSR_IC_AND_SRLZ_D(r8, r9) // reenable the psr.ic bit 223 br.cond.sptk .done 224END(ia64_switch_to) 225 226/* 227 * Note that interrupts are enabled during save_switch_stack and load_switch_stack. This 228 * means that we may get an interrupt with "sp" pointing to the new kernel stack while 229 * ar.bspstore is still pointing to the old kernel backing store area. Since ar.rsc, 230 * ar.rnat, ar.bsp, and ar.bspstore are all preserved by interrupts, this is not a 231 * problem. Also, we don't need to specify unwind information for preserved registers 232 * that are not modified in save_switch_stack as the right unwind information is already 233 * specified at the call-site of save_switch_stack. 234 */ 235 236/* 237 * save_switch_stack: 238 * - r16 holds ar.pfs 239 * - b7 holds address to return to 240 * - rp (b0) holds return address to save 241 */ 242GLOBAL_ENTRY(save_switch_stack) 243 .prologue 244 .altrp b7 245 flushrs // flush dirty regs to backing store (must be first in insn group) 246 .save @priunat,r17 247 mov r17=ar.unat // preserve caller's 248 .body 249#ifdef CONFIG_ITANIUM 250 adds r2=16+128,sp 251 adds r3=16+64,sp 252 adds r14=SW(R4)+16,sp 253 ;; 254 st8.spill [r14]=r4,16 // spill r4 255 lfetch.fault.excl.nt1 [r3],128 256 ;; 257 lfetch.fault.excl.nt1 [r2],128 258 lfetch.fault.excl.nt1 [r3],128 259 ;; 260 lfetch.fault.excl [r2] 261 lfetch.fault.excl [r3] 262 adds r15=SW(R5)+16,sp 263#else 264 add r2=16+3*128,sp 265 add r3=16,sp 266 add r14=SW(R4)+16,sp 267 ;; 268 st8.spill [r14]=r4,SW(R6)-SW(R4) // spill r4 and prefetch offset 0x1c0 269 lfetch.fault.excl.nt1 [r3],128 // prefetch offset 0x010 270 ;; 271 lfetch.fault.excl.nt1 [r3],128 // prefetch offset 0x090 272 lfetch.fault.excl.nt1 [r2],128 // prefetch offset 0x190 273 ;; 274 lfetch.fault.excl.nt1 [r3] // prefetch offset 0x110 275 lfetch.fault.excl.nt1 [r2] // prefetch offset 0x210 276 adds r15=SW(R5)+16,sp 277#endif 278 ;; 279 st8.spill [r15]=r5,SW(R7)-SW(R5) // spill r5 280 mov.m ar.rsc=0 // put RSE in mode: enforced lazy, little endian, pl 0 281 add r2=SW(F2)+16,sp // r2 = &sw->f2 282 ;; 283 st8.spill [r14]=r6,SW(B0)-SW(R6) // spill r6 284 mov.m r18=ar.fpsr // preserve fpsr 285 add r3=SW(F3)+16,sp // r3 = &sw->f3 286 ;; 287 stf.spill [r2]=f2,32 288 mov.m r19=ar.rnat 289 mov r21=b0 290 291 stf.spill [r3]=f3,32 292 st8.spill [r15]=r7,SW(B2)-SW(R7) // spill r7 293 mov r22=b1 294 ;; 295 // since we're done with the spills, read and save ar.unat: 296 mov.m r29=ar.unat 297 mov.m r20=ar.bspstore 298 mov r23=b2 299 stf.spill [r2]=f4,32 300 stf.spill [r3]=f5,32 301 mov r24=b3 302 ;; 303 st8 [r14]=r21,SW(B1)-SW(B0) // save b0 304 st8 [r15]=r23,SW(B3)-SW(B2) // save b2 305 mov r25=b4 306 mov r26=b5 307 ;; 308 st8 [r14]=r22,SW(B4)-SW(B1) // save b1 309 st8 [r15]=r24,SW(AR_PFS)-SW(B3) // save b3 310 mov r21=ar.lc // I-unit 311 stf.spill [r2]=f12,32 312 stf.spill [r3]=f13,32 313 ;; 314 st8 [r14]=r25,SW(B5)-SW(B4) // save b4 315 st8 [r15]=r16,SW(AR_LC)-SW(AR_PFS) // save ar.pfs 316 stf.spill [r2]=f14,32 317 stf.spill [r3]=f15,32 318 ;; 319 st8 [r14]=r26 // save b5 320 st8 [r15]=r21 // save ar.lc 321 stf.spill [r2]=f16,32 322 stf.spill [r3]=f17,32 323 ;; 324 stf.spill [r2]=f18,32 325 stf.spill [r3]=f19,32 326 ;; 327 stf.spill [r2]=f20,32 328 stf.spill [r3]=f21,32 329 ;; 330 stf.spill [r2]=f22,32 331 stf.spill [r3]=f23,32 332 ;; 333 stf.spill [r2]=f24,32 334 stf.spill [r3]=f25,32 335 ;; 336 stf.spill [r2]=f26,32 337 stf.spill [r3]=f27,32 338 ;; 339 stf.spill [r2]=f28,32 340 stf.spill [r3]=f29,32 341 ;; 342 stf.spill [r2]=f30,SW(AR_UNAT)-SW(F30) 343 stf.spill [r3]=f31,SW(PR)-SW(F31) 344 add r14=SW(CALLER_UNAT)+16,sp 345 ;; 346 st8 [r2]=r29,SW(AR_RNAT)-SW(AR_UNAT) // save ar.unat 347 st8 [r14]=r17,SW(AR_FPSR)-SW(CALLER_UNAT) // save caller_unat 348 mov r21=pr 349 ;; 350 st8 [r2]=r19,SW(AR_BSPSTORE)-SW(AR_RNAT) // save ar.rnat 351 st8 [r3]=r21 // save predicate registers 352 ;; 353 st8 [r2]=r20 // save ar.bspstore 354 st8 [r14]=r18 // save fpsr 355 mov ar.rsc=3 // put RSE back into eager mode, pl 0 356 br.cond.sptk.many b7 357END(save_switch_stack) 358 359/* 360 * load_switch_stack: 361 * - "invala" MUST be done at call site (normally in DO_LOAD_SWITCH_STACK) 362 * - b7 holds address to return to 363 * - must not touch r8-r11 364 */ 365GLOBAL_ENTRY(load_switch_stack) 366 .prologue 367 .altrp b7 368 369 .body 370 lfetch.fault.nt1 [sp] 371 adds r2=SW(AR_BSPSTORE)+16,sp 372 adds r3=SW(AR_UNAT)+16,sp 373 mov ar.rsc=0 // put RSE into enforced lazy mode 374 adds r14=SW(CALLER_UNAT)+16,sp 375 adds r15=SW(AR_FPSR)+16,sp 376 ;; 377 ld8 r27=[r2],(SW(B0)-SW(AR_BSPSTORE)) // bspstore 378 ld8 r29=[r3],(SW(B1)-SW(AR_UNAT)) // unat 379 ;; 380 ld8 r21=[r2],16 // restore b0 381 ld8 r22=[r3],16 // restore b1 382 ;; 383 ld8 r23=[r2],16 // restore b2 384 ld8 r24=[r3],16 // restore b3 385 ;; 386 ld8 r25=[r2],16 // restore b4 387 ld8 r26=[r3],16 // restore b5 388 ;; 389 ld8 r16=[r2],(SW(PR)-SW(AR_PFS)) // ar.pfs 390 ld8 r17=[r3],(SW(AR_RNAT)-SW(AR_LC)) // ar.lc 391 ;; 392 ld8 r28=[r2] // restore pr 393 ld8 r30=[r3] // restore rnat 394 ;; 395 ld8 r18=[r14],16 // restore caller's unat 396 ld8 r19=[r15],24 // restore fpsr 397 ;; 398 ldf.fill f2=[r14],32 399 ldf.fill f3=[r15],32 400 ;; 401 ldf.fill f4=[r14],32 402 ldf.fill f5=[r15],32 403 ;; 404 ldf.fill f12=[r14],32 405 ldf.fill f13=[r15],32 406 ;; 407 ldf.fill f14=[r14],32 408 ldf.fill f15=[r15],32 409 ;; 410 ldf.fill f16=[r14],32 411 ldf.fill f17=[r15],32 412 ;; 413 ldf.fill f18=[r14],32 414 ldf.fill f19=[r15],32 415 mov b0=r21 416 ;; 417 ldf.fill f20=[r14],32 418 ldf.fill f21=[r15],32 419 mov b1=r22 420 ;; 421 ldf.fill f22=[r14],32 422 ldf.fill f23=[r15],32 423 mov b2=r23 424 ;; 425 mov ar.bspstore=r27 426 mov ar.unat=r29 // establish unat holding the NaT bits for r4-r7 427 mov b3=r24 428 ;; 429 ldf.fill f24=[r14],32 430 ldf.fill f25=[r15],32 431 mov b4=r25 432 ;; 433 ldf.fill f26=[r14],32 434 ldf.fill f27=[r15],32 435 mov b5=r26 436 ;; 437 ldf.fill f28=[r14],32 438 ldf.fill f29=[r15],32 439 mov ar.pfs=r16 440 ;; 441 ldf.fill f30=[r14],32 442 ldf.fill f31=[r15],24 443 mov ar.lc=r17 444 ;; 445 ld8.fill r4=[r14],16 446 ld8.fill r5=[r15],16 447 mov pr=r28,-1 448 ;; 449 ld8.fill r6=[r14],16 450 ld8.fill r7=[r15],16 451 452 mov ar.unat=r18 // restore caller's unat 453 mov ar.rnat=r30 // must restore after bspstore but before rsc! 454 mov ar.fpsr=r19 // restore fpsr 455 mov ar.rsc=3 // put RSE back into eager mode, pl 0 456 br.cond.sptk.many b7 457END(load_switch_stack) 458 459 /* 460 * Invoke a system call, but do some tracing before and after the call. 461 * We MUST preserve the current register frame throughout this routine 462 * because some system calls (such as ia64_execve) directly 463 * manipulate ar.pfs. 464 */ 465GLOBAL_ENTRY(ia64_trace_syscall) 466 PT_REGS_UNWIND_INFO(0) 467 /* 468 * We need to preserve the scratch registers f6-f11 in case the system 469 * call is sigreturn. 470 */ 471 adds r16=PT(F6)+16,sp 472 adds r17=PT(F7)+16,sp 473 ;; 474 stf.spill [r16]=f6,32 475 stf.spill [r17]=f7,32 476 ;; 477 stf.spill [r16]=f8,32 478 stf.spill [r17]=f9,32 479 ;; 480 stf.spill [r16]=f10 481 stf.spill [r17]=f11 482 br.call.sptk.many rp=syscall_trace_enter // give parent a chance to catch syscall args 483 cmp.lt p6,p0=r8,r0 // check tracehook 484 adds r2=PT(R8)+16,sp // r2 = &pt_regs.r8 485 adds r3=PT(R10)+16,sp // r3 = &pt_regs.r10 486 mov r10=0 487(p6) br.cond.sptk strace_error // syscall failed -> 488 adds r16=PT(F6)+16,sp 489 adds r17=PT(F7)+16,sp 490 ;; 491 ldf.fill f6=[r16],32 492 ldf.fill f7=[r17],32 493 ;; 494 ldf.fill f8=[r16],32 495 ldf.fill f9=[r17],32 496 ;; 497 ldf.fill f10=[r16] 498 ldf.fill f11=[r17] 499 // the syscall number may have changed, so re-load it and re-calculate the 500 // syscall entry-point: 501 adds r15=PT(R15)+16,sp // r15 = &pt_regs.r15 (syscall #) 502 ;; 503 ld8 r15=[r15] 504 mov r3=NR_syscalls - 1 505 ;; 506 adds r15=-1024,r15 507 movl r16=sys_call_table 508 ;; 509 shladd r20=r15,3,r16 // r20 = sys_call_table + 8*(syscall-1024) 510 cmp.leu p6,p7=r15,r3 511 ;; 512(p6) ld8 r20=[r20] // load address of syscall entry point 513(p7) movl r20=sys_ni_syscall 514 ;; 515 mov b6=r20 516 br.call.sptk.many rp=b6 // do the syscall 517.strace_check_retval: 518 cmp.lt p6,p0=r8,r0 // syscall failed? 519 adds r2=PT(R8)+16,sp // r2 = &pt_regs.r8 520 adds r3=PT(R10)+16,sp // r3 = &pt_regs.r10 521 mov r10=0 522(p6) br.cond.sptk strace_error // syscall failed -> 523 ;; // avoid RAW on r10 524.strace_save_retval: 525.mem.offset 0,0; st8.spill [r2]=r8 // store return value in slot for r8 526.mem.offset 8,0; st8.spill [r3]=r10 // clear error indication in slot for r10 527 br.call.sptk.many rp=syscall_trace_leave // give parent a chance to catch return value 528.ret3: 529(pUStk) cmp.eq.unc p6,p0=r0,r0 // p6 <- pUStk 530(pUStk) rsm psr.i // disable interrupts 531 br.cond.sptk ia64_work_pending_syscall_end 532 533strace_error: 534 ld8 r3=[r2] // load pt_regs.r8 535 sub r9=0,r8 // negate return value to get errno value 536 ;; 537 cmp.ne p6,p0=r3,r0 // is pt_regs.r8!=0? 538 adds r3=16,r2 // r3=&pt_regs.r10 539 ;; 540(p6) mov r10=-1 541(p6) mov r8=r9 542 br.cond.sptk .strace_save_retval 543END(ia64_trace_syscall) 544 545 /* 546 * When traced and returning from sigreturn, we invoke syscall_trace but then 547 * go straight to ia64_leave_kernel rather than ia64_leave_syscall. 548 */ 549GLOBAL_ENTRY(ia64_strace_leave_kernel) 550 PT_REGS_UNWIND_INFO(0) 551{ /* 552 * Some versions of gas generate bad unwind info if the first instruction of a 553 * procedure doesn't go into the first slot of a bundle. This is a workaround. 554 */ 555 nop.m 0 556 nop.i 0 557 br.call.sptk.many rp=syscall_trace_leave // give parent a chance to catch return value 558} 559.ret4: br.cond.sptk ia64_leave_kernel 560END(ia64_strace_leave_kernel) 561 562ENTRY(call_payload) 563 .prologue ASM_UNW_PRLG_RP|ASM_UNW_PRLG_PFS, ASM_UNW_PRLG_GRSAVE(0) 564 /* call the kernel_thread payload; fn is in r4, arg - in r5 */ 565 alloc loc1=ar.pfs,0,3,1,0 566 mov loc0=rp 567 mov loc2=gp 568 mov out0=r5 // arg 569 ld8 r14 = [r4], 8 // fn.address 570 ;; 571 mov b6 = r14 572 ld8 gp = [r4] // fn.gp 573 ;; 574 br.call.sptk.many rp=b6 // fn(arg) 575.ret12: mov gp=loc2 576 mov rp=loc0 577 mov ar.pfs=loc1 578 /* ... and if it has returned, we are going to userland */ 579 cmp.ne pKStk,pUStk=r0,r0 580 br.ret.sptk.many rp 581END(call_payload) 582 583GLOBAL_ENTRY(ia64_ret_from_clone) 584 PT_REGS_UNWIND_INFO(0) 585{ /* 586 * Some versions of gas generate bad unwind info if the first instruction of a 587 * procedure doesn't go into the first slot of a bundle. This is a workaround. 588 */ 589 nop.m 0 590 nop.i 0 591 /* 592 * We need to call schedule_tail() to complete the scheduling process. 593 * Called by ia64_switch_to() after do_fork()->copy_thread(). r8 contains the 594 * address of the previously executing task. 595 */ 596 br.call.sptk.many rp=ia64_invoke_schedule_tail 597} 598.ret8: 599(pKStk) br.call.sptk.many rp=call_payload 600 adds r2=TI_FLAGS+IA64_TASK_SIZE,r13 601 ;; 602 ld4 r2=[r2] 603 ;; 604 mov r8=0 605 and r2=_TIF_SYSCALL_TRACEAUDIT,r2 606 ;; 607 cmp.ne p6,p0=r2,r0 608(p6) br.cond.spnt .strace_check_retval 609 ;; // added stop bits to prevent r8 dependency 610END(ia64_ret_from_clone) 611 // fall through 612GLOBAL_ENTRY(ia64_ret_from_syscall) 613 PT_REGS_UNWIND_INFO(0) 614 cmp.ge p6,p7=r8,r0 // syscall executed successfully? 615 adds r2=PT(R8)+16,sp // r2 = &pt_regs.r8 616 mov r10=r0 // clear error indication in r10 617(p7) br.cond.spnt handle_syscall_error // handle potential syscall failure 618END(ia64_ret_from_syscall) 619 // fall through 620 621/* 622 * ia64_leave_syscall(): Same as ia64_leave_kernel, except that it doesn't 623 * need to switch to bank 0 and doesn't restore the scratch registers. 624 * To avoid leaking kernel bits, the scratch registers are set to 625 * the following known-to-be-safe values: 626 * 627 * r1: restored (global pointer) 628 * r2: cleared 629 * r3: 1 (when returning to user-level) 630 * r8-r11: restored (syscall return value(s)) 631 * r12: restored (user-level stack pointer) 632 * r13: restored (user-level thread pointer) 633 * r14: set to __kernel_syscall_via_epc 634 * r15: restored (syscall #) 635 * r16-r17: cleared 636 * r18: user-level b6 637 * r19: cleared 638 * r20: user-level ar.fpsr 639 * r21: user-level b0 640 * r22: cleared 641 * r23: user-level ar.bspstore 642 * r24: user-level ar.rnat 643 * r25: user-level ar.unat 644 * r26: user-level ar.pfs 645 * r27: user-level ar.rsc 646 * r28: user-level ip 647 * r29: user-level psr 648 * r30: user-level cfm 649 * r31: user-level pr 650 * f6-f11: cleared 651 * pr: restored (user-level pr) 652 * b0: restored (user-level rp) 653 * b6: restored 654 * b7: set to __kernel_syscall_via_epc 655 * ar.unat: restored (user-level ar.unat) 656 * ar.pfs: restored (user-level ar.pfs) 657 * ar.rsc: restored (user-level ar.rsc) 658 * ar.rnat: restored (user-level ar.rnat) 659 * ar.bspstore: restored (user-level ar.bspstore) 660 * ar.fpsr: restored (user-level ar.fpsr) 661 * ar.ccv: cleared 662 * ar.csd: cleared 663 * ar.ssd: cleared 664 */ 665GLOBAL_ENTRY(ia64_leave_syscall) 666 PT_REGS_UNWIND_INFO(0) 667 /* 668 * work.need_resched etc. mustn't get changed by this CPU before it returns to 669 * user- or fsys-mode, hence we disable interrupts early on. 670 * 671 * p6 controls whether current_thread_info()->flags needs to be check for 672 * extra work. We always check for extra work when returning to user-level. 673 * With CONFIG_PREEMPTION, we also check for extra work when the preempt_count 674 * is 0. After extra work processing has been completed, execution 675 * resumes at ia64_work_processed_syscall with p6 set to 1 if the extra-work-check 676 * needs to be redone. 677 */ 678#ifdef CONFIG_PREEMPTION 679 RSM_PSR_I(p0, r2, r18) // disable interrupts 680 cmp.eq pLvSys,p0=r0,r0 // pLvSys=1: leave from syscall 681(pKStk) adds r20=TI_PRE_COUNT+IA64_TASK_SIZE,r13 682 ;; 683 .pred.rel.mutex pUStk,pKStk 684(pKStk) ld4 r21=[r20] // r21 <- preempt_count 685(pUStk) mov r21=0 // r21 <- 0 686 ;; 687 cmp.eq p6,p0=r21,r0 // p6 <- pUStk || (preempt_count == 0) 688#else /* !CONFIG_PREEMPTION */ 689 RSM_PSR_I(pUStk, r2, r18) 690 cmp.eq pLvSys,p0=r0,r0 // pLvSys=1: leave from syscall 691(pUStk) cmp.eq.unc p6,p0=r0,r0 // p6 <- pUStk 692#endif 693.global ia64_work_processed_syscall; 694ia64_work_processed_syscall: 695#ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE 696 adds r2=PT(LOADRS)+16,r12 697 MOV_FROM_ITC(pUStk, p9, r22, r19) // fetch time at leave 698 adds r18=TI_FLAGS+IA64_TASK_SIZE,r13 699 ;; 700(p6) ld4 r31=[r18] // load current_thread_info()->flags 701 ld8 r19=[r2],PT(B6)-PT(LOADRS) // load ar.rsc value for "loadrs" 702 adds r3=PT(AR_BSPSTORE)+16,r12 // deferred 703 ;; 704#else 705 adds r2=PT(LOADRS)+16,r12 706 adds r3=PT(AR_BSPSTORE)+16,r12 707 adds r18=TI_FLAGS+IA64_TASK_SIZE,r13 708 ;; 709(p6) ld4 r31=[r18] // load current_thread_info()->flags 710 ld8 r19=[r2],PT(B6)-PT(LOADRS) // load ar.rsc value for "loadrs" 711 nop.i 0 712 ;; 713#endif 714 mov r16=ar.bsp // M2 get existing backing store pointer 715 ld8 r18=[r2],PT(R9)-PT(B6) // load b6 716(p6) and r15=TIF_WORK_MASK,r31 // any work other than TIF_SYSCALL_TRACE? 717 ;; 718 ld8 r23=[r3],PT(R11)-PT(AR_BSPSTORE) // load ar.bspstore (may be garbage) 719(p6) cmp4.ne.unc p6,p0=r15, r0 // any special work pending? 720(p6) br.cond.spnt .work_pending_syscall 721 ;; 722 // start restoring the state saved on the kernel stack (struct pt_regs): 723 ld8 r9=[r2],PT(CR_IPSR)-PT(R9) 724 ld8 r11=[r3],PT(CR_IIP)-PT(R11) 725(pNonSys) break 0 // bug check: we shouldn't be here if pNonSys is TRUE! 726 ;; 727 invala // M0|1 invalidate ALAT 728 RSM_PSR_I_IC(r28, r29, r30) // M2 turn off interrupts and interruption collection 729 cmp.eq p9,p0=r0,r0 // A set p9 to indicate that we should restore cr.ifs 730 731 ld8 r29=[r2],16 // M0|1 load cr.ipsr 732 ld8 r28=[r3],16 // M0|1 load cr.iip 733#ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE 734(pUStk) add r14=TI_AC_LEAVE+IA64_TASK_SIZE,r13 735 ;; 736 ld8 r30=[r2],16 // M0|1 load cr.ifs 737 ld8 r25=[r3],16 // M0|1 load ar.unat 738(pUStk) add r15=IA64_TASK_THREAD_ON_USTACK_OFFSET,r13 739 ;; 740#else 741 mov r22=r0 // A clear r22 742 ;; 743 ld8 r30=[r2],16 // M0|1 load cr.ifs 744 ld8 r25=[r3],16 // M0|1 load ar.unat 745(pUStk) add r14=IA64_TASK_THREAD_ON_USTACK_OFFSET,r13 746 ;; 747#endif 748 ld8 r26=[r2],PT(B0)-PT(AR_PFS) // M0|1 load ar.pfs 749 MOV_FROM_PSR(pKStk, r22, r21) // M2 read PSR now that interrupts are disabled 750 nop 0 751 ;; 752 ld8 r21=[r2],PT(AR_RNAT)-PT(B0) // M0|1 load b0 753 ld8 r27=[r3],PT(PR)-PT(AR_RSC) // M0|1 load ar.rsc 754 mov f6=f0 // F clear f6 755 ;; 756 ld8 r24=[r2],PT(AR_FPSR)-PT(AR_RNAT) // M0|1 load ar.rnat (may be garbage) 757 ld8 r31=[r3],PT(R1)-PT(PR) // M0|1 load predicates 758 mov f7=f0 // F clear f7 759 ;; 760 ld8 r20=[r2],PT(R12)-PT(AR_FPSR) // M0|1 load ar.fpsr 761 ld8.fill r1=[r3],16 // M0|1 load r1 762(pUStk) mov r17=1 // A 763 ;; 764#ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE 765(pUStk) st1 [r15]=r17 // M2|3 766#else 767(pUStk) st1 [r14]=r17 // M2|3 768#endif 769 ld8.fill r13=[r3],16 // M0|1 770 mov f8=f0 // F clear f8 771 ;; 772 ld8.fill r12=[r2] // M0|1 restore r12 (sp) 773 ld8.fill r15=[r3] // M0|1 restore r15 774 mov b6=r18 // I0 restore b6 775 776 LOAD_PHYS_STACK_REG_SIZE(r17) 777 mov f9=f0 // F clear f9 778(pKStk) br.cond.dpnt.many skip_rbs_switch // B 779 780 srlz.d // M0 ensure interruption collection is off (for cover) 781 shr.u r18=r19,16 // I0|1 get byte size of existing "dirty" partition 782 COVER // B add current frame into dirty partition & set cr.ifs 783 ;; 784#ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE 785 mov r19=ar.bsp // M2 get new backing store pointer 786 st8 [r14]=r22 // M save time at leave 787 mov f10=f0 // F clear f10 788 789 mov r22=r0 // A clear r22 790 movl r14=__kernel_syscall_via_epc // X 791 ;; 792#else 793 mov r19=ar.bsp // M2 get new backing store pointer 794 mov f10=f0 // F clear f10 795 796 nop.m 0 797 movl r14=__kernel_syscall_via_epc // X 798 ;; 799#endif 800 mov.m ar.csd=r0 // M2 clear ar.csd 801 mov.m ar.ccv=r0 // M2 clear ar.ccv 802 mov b7=r14 // I0 clear b7 (hint with __kernel_syscall_via_epc) 803 804 mov.m ar.ssd=r0 // M2 clear ar.ssd 805 mov f11=f0 // F clear f11 806 br.cond.sptk.many rbs_switch // B 807END(ia64_leave_syscall) 808 809GLOBAL_ENTRY(ia64_leave_kernel) 810 PT_REGS_UNWIND_INFO(0) 811 /* 812 * work.need_resched etc. mustn't get changed by this CPU before it returns to 813 * user- or fsys-mode, hence we disable interrupts early on. 814 * 815 * p6 controls whether current_thread_info()->flags needs to be check for 816 * extra work. We always check for extra work when returning to user-level. 817 * With CONFIG_PREEMPTION, we also check for extra work when the preempt_count 818 * is 0. After extra work processing has been completed, execution 819 * resumes at .work_processed_syscall with p6 set to 1 if the extra-work-check 820 * needs to be redone. 821 */ 822#ifdef CONFIG_PREEMPTION 823 RSM_PSR_I(p0, r17, r31) // disable interrupts 824 cmp.eq p0,pLvSys=r0,r0 // pLvSys=0: leave from kernel 825(pKStk) adds r20=TI_PRE_COUNT+IA64_TASK_SIZE,r13 826 ;; 827 .pred.rel.mutex pUStk,pKStk 828(pKStk) ld4 r21=[r20] // r21 <- preempt_count 829(pUStk) mov r21=0 // r21 <- 0 830 ;; 831 cmp.eq p6,p0=r21,r0 // p6 <- pUStk || (preempt_count == 0) 832#else 833 RSM_PSR_I(pUStk, r17, r31) 834 cmp.eq p0,pLvSys=r0,r0 // pLvSys=0: leave from kernel 835(pUStk) cmp.eq.unc p6,p0=r0,r0 // p6 <- pUStk 836#endif 837.work_processed_kernel: 838 adds r17=TI_FLAGS+IA64_TASK_SIZE,r13 839 ;; 840(p6) ld4 r31=[r17] // load current_thread_info()->flags 841 adds r21=PT(PR)+16,r12 842 ;; 843 844 lfetch [r21],PT(CR_IPSR)-PT(PR) 845 adds r2=PT(B6)+16,r12 846 adds r3=PT(R16)+16,r12 847 ;; 848 lfetch [r21] 849 ld8 r28=[r2],8 // load b6 850 adds r29=PT(R24)+16,r12 851 852 ld8.fill r16=[r3],PT(AR_CSD)-PT(R16) 853 adds r30=PT(AR_CCV)+16,r12 854(p6) and r19=TIF_WORK_MASK,r31 // any work other than TIF_SYSCALL_TRACE? 855 ;; 856 ld8.fill r24=[r29] 857 ld8 r15=[r30] // load ar.ccv 858(p6) cmp4.ne.unc p6,p0=r19, r0 // any special work pending? 859 ;; 860 ld8 r29=[r2],16 // load b7 861 ld8 r30=[r3],16 // load ar.csd 862(p6) br.cond.spnt .work_pending 863 ;; 864 ld8 r31=[r2],16 // load ar.ssd 865 ld8.fill r8=[r3],16 866 ;; 867 ld8.fill r9=[r2],16 868 ld8.fill r10=[r3],PT(R17)-PT(R10) 869 ;; 870 ld8.fill r11=[r2],PT(R18)-PT(R11) 871 ld8.fill r17=[r3],16 872 ;; 873 ld8.fill r18=[r2],16 874 ld8.fill r19=[r3],16 875 ;; 876 ld8.fill r20=[r2],16 877 ld8.fill r21=[r3],16 878 mov ar.csd=r30 879 mov ar.ssd=r31 880 ;; 881 RSM_PSR_I_IC(r23, r22, r25) // initiate turning off of interrupt and interruption collection 882 invala // invalidate ALAT 883 ;; 884 ld8.fill r22=[r2],24 885 ld8.fill r23=[r3],24 886 mov b6=r28 887 ;; 888 ld8.fill r25=[r2],16 889 ld8.fill r26=[r3],16 890 mov b7=r29 891 ;; 892 ld8.fill r27=[r2],16 893 ld8.fill r28=[r3],16 894 ;; 895 ld8.fill r29=[r2],16 896 ld8.fill r30=[r3],24 897 ;; 898 ld8.fill r31=[r2],PT(F9)-PT(R31) 899 adds r3=PT(F10)-PT(F6),r3 900 ;; 901 ldf.fill f9=[r2],PT(F6)-PT(F9) 902 ldf.fill f10=[r3],PT(F8)-PT(F10) 903 ;; 904 ldf.fill f6=[r2],PT(F7)-PT(F6) 905 ;; 906 ldf.fill f7=[r2],PT(F11)-PT(F7) 907 ldf.fill f8=[r3],32 908 ;; 909 srlz.d // ensure that inter. collection is off (VHPT is don't care, since text is pinned) 910 mov ar.ccv=r15 911 ;; 912 ldf.fill f11=[r2] 913 BSW_0(r2, r3, r15) // switch back to bank 0 (no stop bit required beforehand...) 914 ;; 915(pUStk) mov r18=IA64_KR(CURRENT)// M2 (12 cycle read latency) 916 adds r16=PT(CR_IPSR)+16,r12 917 adds r17=PT(CR_IIP)+16,r12 918 919#ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE 920 .pred.rel.mutex pUStk,pKStk 921 MOV_FROM_PSR(pKStk, r22, r29) // M2 read PSR now that interrupts are disabled 922 MOV_FROM_ITC(pUStk, p9, r22, r29) // M fetch time at leave 923 nop.i 0 924 ;; 925#else 926 MOV_FROM_PSR(pKStk, r22, r29) // M2 read PSR now that interrupts are disabled 927 nop.i 0 928 nop.i 0 929 ;; 930#endif 931 ld8 r29=[r16],16 // load cr.ipsr 932 ld8 r28=[r17],16 // load cr.iip 933 ;; 934 ld8 r30=[r16],16 // load cr.ifs 935 ld8 r25=[r17],16 // load ar.unat 936 ;; 937 ld8 r26=[r16],16 // load ar.pfs 938 ld8 r27=[r17],16 // load ar.rsc 939 cmp.eq p9,p0=r0,r0 // set p9 to indicate that we should restore cr.ifs 940 ;; 941 ld8 r24=[r16],16 // load ar.rnat (may be garbage) 942 ld8 r23=[r17],16 // load ar.bspstore (may be garbage) 943 ;; 944 ld8 r31=[r16],16 // load predicates 945 ld8 r21=[r17],16 // load b0 946 ;; 947 ld8 r19=[r16],16 // load ar.rsc value for "loadrs" 948 ld8.fill r1=[r17],16 // load r1 949 ;; 950 ld8.fill r12=[r16],16 951 ld8.fill r13=[r17],16 952#ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE 953(pUStk) adds r3=TI_AC_LEAVE+IA64_TASK_SIZE,r18 954#else 955(pUStk) adds r18=IA64_TASK_THREAD_ON_USTACK_OFFSET,r18 956#endif 957 ;; 958 ld8 r20=[r16],16 // ar.fpsr 959 ld8.fill r15=[r17],16 960#ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE 961(pUStk) adds r18=IA64_TASK_THREAD_ON_USTACK_OFFSET,r18 // deferred 962#endif 963 ;; 964 ld8.fill r14=[r16],16 965 ld8.fill r2=[r17] 966(pUStk) mov r17=1 967 ;; 968#ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE 969 // mmi_ : ld8 st1 shr;; mmi_ : st8 st1 shr;; 970 // mib : mov add br -> mib : ld8 add br 971 // bbb_ : br nop cover;; mbb_ : mov br cover;; 972 // 973 // no one require bsp in r16 if (pKStk) branch is selected. 974(pUStk) st8 [r3]=r22 // save time at leave 975(pUStk) st1 [r18]=r17 // restore current->thread.on_ustack 976 shr.u r18=r19,16 // get byte size of existing "dirty" partition 977 ;; 978 ld8.fill r3=[r16] // deferred 979 LOAD_PHYS_STACK_REG_SIZE(r17) 980(pKStk) br.cond.dpnt skip_rbs_switch 981 mov r16=ar.bsp // get existing backing store pointer 982#else 983 ld8.fill r3=[r16] 984(pUStk) st1 [r18]=r17 // restore current->thread.on_ustack 985 shr.u r18=r19,16 // get byte size of existing "dirty" partition 986 ;; 987 mov r16=ar.bsp // get existing backing store pointer 988 LOAD_PHYS_STACK_REG_SIZE(r17) 989(pKStk) br.cond.dpnt skip_rbs_switch 990#endif 991 992 /* 993 * Restore user backing store. 994 * 995 * NOTE: alloc, loadrs, and cover can't be predicated. 996 */ 997(pNonSys) br.cond.dpnt dont_preserve_current_frame 998 COVER // add current frame into dirty partition and set cr.ifs 999 ;; 1000 mov r19=ar.bsp // get new backing store pointer 1001rbs_switch: 1002 sub r16=r16,r18 // krbs = old bsp - size of dirty partition 1003 cmp.ne p9,p0=r0,r0 // clear p9 to skip restore of cr.ifs 1004 ;; 1005 sub r19=r19,r16 // calculate total byte size of dirty partition 1006 add r18=64,r18 // don't force in0-in7 into memory... 1007 ;; 1008 shl r19=r19,16 // shift size of dirty partition into loadrs position 1009 ;; 1010dont_preserve_current_frame: 1011 /* 1012 * To prevent leaking bits between the kernel and user-space, 1013 * we must clear the stacked registers in the "invalid" partition here. 1014 * Not pretty, but at least it's fast (3.34 registers/cycle on Itanium, 1015 * 5 registers/cycle on McKinley). 1016 */ 1017# define pRecurse p6 1018# define pReturn p7 1019#ifdef CONFIG_ITANIUM 1020# define Nregs 10 1021#else 1022# define Nregs 14 1023#endif 1024 alloc loc0=ar.pfs,2,Nregs-2,2,0 1025 shr.u loc1=r18,9 // RNaTslots <= floor(dirtySize / (64*8)) 1026 sub r17=r17,r18 // r17 = (physStackedSize + 8) - dirtySize 1027 ;; 1028 mov ar.rsc=r19 // load ar.rsc to be used for "loadrs" 1029 shladd in0=loc1,3,r17 1030 mov in1=0 1031 ;; 1032 TEXT_ALIGN(32) 1033rse_clear_invalid: 1034#ifdef CONFIG_ITANIUM 1035 // cycle 0 1036 { .mii 1037 alloc loc0=ar.pfs,2,Nregs-2,2,0 1038 cmp.lt pRecurse,p0=Nregs*8,in0 // if more than Nregs regs left to clear, (re)curse 1039 add out0=-Nregs*8,in0 1040}{ .mfb 1041 add out1=1,in1 // increment recursion count 1042 nop.f 0 1043 nop.b 0 // can't do br.call here because of alloc (WAW on CFM) 1044 ;; 1045}{ .mfi // cycle 1 1046 mov loc1=0 1047 nop.f 0 1048 mov loc2=0 1049}{ .mib 1050 mov loc3=0 1051 mov loc4=0 1052(pRecurse) br.call.sptk.many b0=rse_clear_invalid 1053 1054}{ .mfi // cycle 2 1055 mov loc5=0 1056 nop.f 0 1057 cmp.ne pReturn,p0=r0,in1 // if recursion count != 0, we need to do a br.ret 1058}{ .mib 1059 mov loc6=0 1060 mov loc7=0 1061(pReturn) br.ret.sptk.many b0 1062} 1063#else /* !CONFIG_ITANIUM */ 1064 alloc loc0=ar.pfs,2,Nregs-2,2,0 1065 cmp.lt pRecurse,p0=Nregs*8,in0 // if more than Nregs regs left to clear, (re)curse 1066 add out0=-Nregs*8,in0 1067 add out1=1,in1 // increment recursion count 1068 mov loc1=0 1069 mov loc2=0 1070 ;; 1071 mov loc3=0 1072 mov loc4=0 1073 mov loc5=0 1074 mov loc6=0 1075 mov loc7=0 1076(pRecurse) br.call.dptk.few b0=rse_clear_invalid 1077 ;; 1078 mov loc8=0 1079 mov loc9=0 1080 cmp.ne pReturn,p0=r0,in1 // if recursion count != 0, we need to do a br.ret 1081 mov loc10=0 1082 mov loc11=0 1083(pReturn) br.ret.dptk.many b0 1084#endif /* !CONFIG_ITANIUM */ 1085# undef pRecurse 1086# undef pReturn 1087 ;; 1088 alloc r17=ar.pfs,0,0,0,0 // drop current register frame 1089 ;; 1090 loadrs 1091 ;; 1092skip_rbs_switch: 1093 mov ar.unat=r25 // M2 1094(pKStk) extr.u r22=r22,21,1 // I0 extract current value of psr.pp from r22 1095(pLvSys)mov r19=r0 // A clear r19 for leave_syscall, no-op otherwise 1096 ;; 1097(pUStk) mov ar.bspstore=r23 // M2 1098(pKStk) dep r29=r22,r29,21,1 // I0 update ipsr.pp with psr.pp 1099(pLvSys)mov r16=r0 // A clear r16 for leave_syscall, no-op otherwise 1100 ;; 1101 MOV_TO_IPSR(p0, r29, r25) // M2 1102 mov ar.pfs=r26 // I0 1103(pLvSys)mov r17=r0 // A clear r17 for leave_syscall, no-op otherwise 1104 1105 MOV_TO_IFS(p9, r30, r25)// M2 1106 mov b0=r21 // I0 1107(pLvSys)mov r18=r0 // A clear r18 for leave_syscall, no-op otherwise 1108 1109 mov ar.fpsr=r20 // M2 1110 MOV_TO_IIP(r28, r25) // M2 1111 nop 0 1112 ;; 1113(pUStk) mov ar.rnat=r24 // M2 must happen with RSE in lazy mode 1114 nop 0 1115(pLvSys)mov r2=r0 1116 1117 mov ar.rsc=r27 // M2 1118 mov pr=r31,-1 // I0 1119 RFI // B 1120 1121 /* 1122 * On entry: 1123 * r20 = ¤t->thread_info->pre_count (if CONFIG_PREEMPTION) 1124 * r31 = current->thread_info->flags 1125 * On exit: 1126 * p6 = TRUE if work-pending-check needs to be redone 1127 * 1128 * Interrupts are disabled on entry, reenabled depend on work, and 1129 * disabled on exit. 1130 */ 1131.work_pending_syscall: 1132 add r2=-8,r2 1133 add r3=-8,r3 1134 ;; 1135 st8 [r2]=r8 1136 st8 [r3]=r10 1137.work_pending: 1138 tbit.z p6,p0=r31,TIF_NEED_RESCHED // is resched not needed? 1139(p6) br.cond.sptk.few .notify 1140 br.call.spnt.many rp=preempt_schedule_irq 1141.ret9: cmp.eq p6,p0=r0,r0 // p6 <- 1 (re-check) 1142(pLvSys)br.cond.sptk.few ia64_work_pending_syscall_end 1143 br.cond.sptk.many .work_processed_kernel 1144 1145.notify: 1146(pUStk) br.call.spnt.many rp=notify_resume_user 1147.ret10: cmp.ne p6,p0=r0,r0 // p6 <- 0 (don't re-check) 1148(pLvSys)br.cond.sptk.few ia64_work_pending_syscall_end 1149 br.cond.sptk.many .work_processed_kernel 1150 1151.global ia64_work_pending_syscall_end; 1152ia64_work_pending_syscall_end: 1153 adds r2=PT(R8)+16,r12 1154 adds r3=PT(R10)+16,r12 1155 ;; 1156 ld8 r8=[r2] 1157 ld8 r10=[r3] 1158 br.cond.sptk.many ia64_work_processed_syscall 1159END(ia64_leave_kernel) 1160 1161ENTRY(handle_syscall_error) 1162 /* 1163 * Some system calls (e.g., ptrace, mmap) can return arbitrary values which could 1164 * lead us to mistake a negative return value as a failed syscall. Those syscall 1165 * must deposit a non-zero value in pt_regs.r8 to indicate an error. If 1166 * pt_regs.r8 is zero, we assume that the call completed successfully. 1167 */ 1168 PT_REGS_UNWIND_INFO(0) 1169 ld8 r3=[r2] // load pt_regs.r8 1170 ;; 1171 cmp.eq p6,p7=r3,r0 // is pt_regs.r8==0? 1172 ;; 1173(p7) mov r10=-1 1174(p7) sub r8=0,r8 // negate return value to get errno 1175 br.cond.sptk ia64_leave_syscall 1176END(handle_syscall_error) 1177 1178 /* 1179 * Invoke schedule_tail(task) while preserving in0-in7, which may be needed 1180 * in case a system call gets restarted. 1181 */ 1182GLOBAL_ENTRY(ia64_invoke_schedule_tail) 1183 .prologue ASM_UNW_PRLG_RP|ASM_UNW_PRLG_PFS, ASM_UNW_PRLG_GRSAVE(8) 1184 alloc loc1=ar.pfs,8,2,1,0 1185 mov loc0=rp 1186 mov out0=r8 // Address of previous task 1187 ;; 1188 br.call.sptk.many rp=schedule_tail 1189.ret11: mov ar.pfs=loc1 1190 mov rp=loc0 1191 br.ret.sptk.many rp 1192END(ia64_invoke_schedule_tail) 1193 1194 /* 1195 * Setup stack and call do_notify_resume_user(), keeping interrupts 1196 * disabled. 1197 * 1198 * Note that pSys and pNonSys need to be set up by the caller. 1199 * We declare 8 input registers so the system call args get preserved, 1200 * in case we need to restart a system call. 1201 */ 1202GLOBAL_ENTRY(notify_resume_user) 1203 .prologue ASM_UNW_PRLG_RP|ASM_UNW_PRLG_PFS, ASM_UNW_PRLG_GRSAVE(8) 1204 alloc loc1=ar.pfs,8,2,3,0 // preserve all eight input regs in case of syscall restart! 1205 mov r9=ar.unat 1206 mov loc0=rp // save return address 1207 mov out0=0 // there is no "oldset" 1208 adds out1=8,sp // out1=&sigscratch->ar_pfs 1209(pSys) mov out2=1 // out2==1 => we're in a syscall 1210 ;; 1211(pNonSys) mov out2=0 // out2==0 => not a syscall 1212 .fframe 16 1213 .spillsp ar.unat, 16 1214 st8 [sp]=r9,-16 // allocate space for ar.unat and save it 1215 st8 [out1]=loc1,-8 // save ar.pfs, out1=&sigscratch 1216 .body 1217 br.call.sptk.many rp=do_notify_resume_user 1218.ret15: .restore sp 1219 adds sp=16,sp // pop scratch stack space 1220 ;; 1221 ld8 r9=[sp] // load new unat from sigscratch->scratch_unat 1222 mov rp=loc0 1223 ;; 1224 mov ar.unat=r9 1225 mov ar.pfs=loc1 1226 br.ret.sptk.many rp 1227END(notify_resume_user) 1228 1229ENTRY(sys_rt_sigreturn) 1230 PT_REGS_UNWIND_INFO(0) 1231 /* 1232 * Allocate 8 input registers since ptrace() may clobber them 1233 */ 1234 alloc r2=ar.pfs,8,0,1,0 1235 .prologue 1236 PT_REGS_SAVES(16) 1237 adds sp=-16,sp 1238 .body 1239 cmp.eq pNonSys,pSys=r0,r0 // sigreturn isn't a normal syscall... 1240 ;; 1241 /* 1242 * leave_kernel() restores f6-f11 from pt_regs, but since the streamlined 1243 * syscall-entry path does not save them we save them here instead. Note: we 1244 * don't need to save any other registers that are not saved by the stream-lined 1245 * syscall path, because restore_sigcontext() restores them. 1246 */ 1247 adds r16=PT(F6)+32,sp 1248 adds r17=PT(F7)+32,sp 1249 ;; 1250 stf.spill [r16]=f6,32 1251 stf.spill [r17]=f7,32 1252 ;; 1253 stf.spill [r16]=f8,32 1254 stf.spill [r17]=f9,32 1255 ;; 1256 stf.spill [r16]=f10 1257 stf.spill [r17]=f11 1258 adds out0=16,sp // out0 = &sigscratch 1259 br.call.sptk.many rp=ia64_rt_sigreturn 1260.ret19: .restore sp,0 1261 adds sp=16,sp 1262 ;; 1263 ld8 r9=[sp] // load new ar.unat 1264 mov.sptk b7=r8,ia64_leave_kernel 1265 ;; 1266 mov ar.unat=r9 1267 br.many b7 1268END(sys_rt_sigreturn) 1269 1270GLOBAL_ENTRY(ia64_prepare_handle_unaligned) 1271 .prologue 1272 /* 1273 * r16 = fake ar.pfs, we simply need to make sure privilege is still 0 1274 */ 1275 mov r16=r0 1276 DO_SAVE_SWITCH_STACK 1277 br.call.sptk.many rp=ia64_handle_unaligned // stack frame setup in ivt 1278.ret21: .body 1279 DO_LOAD_SWITCH_STACK 1280 br.cond.sptk.many rp // goes to ia64_leave_kernel 1281END(ia64_prepare_handle_unaligned) 1282 1283 // 1284 // unw_init_running(void (*callback)(info, arg), void *arg) 1285 // 1286# define EXTRA_FRAME_SIZE ((UNW_FRAME_INFO_SIZE+15)&~15) 1287 1288GLOBAL_ENTRY(unw_init_running) 1289 .prologue ASM_UNW_PRLG_RP|ASM_UNW_PRLG_PFS, ASM_UNW_PRLG_GRSAVE(2) 1290 alloc loc1=ar.pfs,2,3,3,0 1291 ;; 1292 ld8 loc2=[in0],8 1293 mov loc0=rp 1294 mov r16=loc1 1295 DO_SAVE_SWITCH_STACK 1296 .body 1297 1298 .prologue ASM_UNW_PRLG_RP|ASM_UNW_PRLG_PFS, ASM_UNW_PRLG_GRSAVE(2) 1299 .fframe IA64_SWITCH_STACK_SIZE+EXTRA_FRAME_SIZE 1300 SWITCH_STACK_SAVES(EXTRA_FRAME_SIZE) 1301 adds sp=-EXTRA_FRAME_SIZE,sp 1302 .body 1303 ;; 1304 adds out0=16,sp // &info 1305 mov out1=r13 // current 1306 adds out2=16+EXTRA_FRAME_SIZE,sp // &switch_stack 1307 br.call.sptk.many rp=unw_init_frame_info 13081: adds out0=16,sp // &info 1309 mov b6=loc2 1310 mov loc2=gp // save gp across indirect function call 1311 ;; 1312 ld8 gp=[in0] 1313 mov out1=in1 // arg 1314 br.call.sptk.many rp=b6 // invoke the callback function 13151: mov gp=loc2 // restore gp 1316 1317 // For now, we don't allow changing registers from within 1318 // unw_init_running; if we ever want to allow that, we'd 1319 // have to do a load_switch_stack here: 1320 .restore sp 1321 adds sp=IA64_SWITCH_STACK_SIZE+EXTRA_FRAME_SIZE,sp 1322 1323 mov ar.pfs=loc1 1324 mov rp=loc0 1325 br.ret.sptk.many rp 1326END(unw_init_running) 1327EXPORT_SYMBOL(unw_init_running) 1328 1329#ifdef CONFIG_FUNCTION_TRACER 1330#ifdef CONFIG_DYNAMIC_FTRACE 1331GLOBAL_ENTRY(_mcount) 1332 br ftrace_stub 1333END(_mcount) 1334EXPORT_SYMBOL(_mcount) 1335 1336.here: 1337 br.ret.sptk.many b0 1338 1339GLOBAL_ENTRY(ftrace_caller) 1340 alloc out0 = ar.pfs, 8, 0, 4, 0 1341 mov out3 = r0 1342 ;; 1343 mov out2 = b0 1344 add r3 = 0x20, r3 1345 mov out1 = r1; 1346 br.call.sptk.many b0 = ftrace_patch_gp 1347 //this might be called from module, so we must patch gp 1348ftrace_patch_gp: 1349 movl gp=__gp 1350 mov b0 = r3 1351 ;; 1352.global ftrace_call; 1353ftrace_call: 1354{ 1355 .mlx 1356 nop.m 0x0 1357 movl r3 = .here;; 1358} 1359 alloc loc0 = ar.pfs, 4, 4, 2, 0 1360 ;; 1361 mov loc1 = b0 1362 mov out0 = b0 1363 mov loc2 = r8 1364 mov loc3 = r15 1365 ;; 1366 adds out0 = -MCOUNT_INSN_SIZE, out0 1367 mov out1 = in2 1368 mov b6 = r3 1369 1370 br.call.sptk.many b0 = b6 1371 ;; 1372 mov ar.pfs = loc0 1373 mov b0 = loc1 1374 mov r8 = loc2 1375 mov r15 = loc3 1376 br ftrace_stub 1377 ;; 1378END(ftrace_caller) 1379 1380#else 1381GLOBAL_ENTRY(_mcount) 1382 movl r2 = ftrace_stub 1383 movl r3 = ftrace_trace_function;; 1384 ld8 r3 = [r3];; 1385 ld8 r3 = [r3];; 1386 cmp.eq p7,p0 = r2, r3 1387(p7) br.sptk.many ftrace_stub 1388 ;; 1389 1390 alloc loc0 = ar.pfs, 4, 4, 2, 0 1391 ;; 1392 mov loc1 = b0 1393 mov out0 = b0 1394 mov loc2 = r8 1395 mov loc3 = r15 1396 ;; 1397 adds out0 = -MCOUNT_INSN_SIZE, out0 1398 mov out1 = in2 1399 mov b6 = r3 1400 1401 br.call.sptk.many b0 = b6 1402 ;; 1403 mov ar.pfs = loc0 1404 mov b0 = loc1 1405 mov r8 = loc2 1406 mov r15 = loc3 1407 br ftrace_stub 1408 ;; 1409END(_mcount) 1410#endif 1411 1412GLOBAL_ENTRY(ftrace_stub) 1413 mov r3 = b0 1414 movl r2 = _mcount_ret_helper 1415 ;; 1416 mov b6 = r2 1417 mov b7 = r3 1418 br.ret.sptk.many b6 1419 1420_mcount_ret_helper: 1421 mov b0 = r42 1422 mov r1 = r41 1423 mov ar.pfs = r40 1424 br b7 1425END(ftrace_stub) 1426 1427#endif /* CONFIG_FUNCTION_TRACER */ 1428 1429#define __SYSCALL(nr, entry, nargs) data8 entry 1430 .rodata 1431 .align 8 1432 .globl sys_call_table 1433sys_call_table: 1434#include <asm/syscall_table.h> 1435#undef __SYSCALL 1436