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+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * arch/ia64/kernel/entry.S
+ *
+ * Kernel entry points.
+ *
+ * Copyright (C) 1998-2003, 2005 Hewlett-Packard Co
+ * David Mosberger-Tang <davidm@hpl.hp.com>
+ * Copyright (C) 1999, 2002-2003
+ * Asit Mallick <Asit.K.Mallick@intel.com>
+ * Don Dugger <Don.Dugger@intel.com>
+ * Suresh Siddha <suresh.b.siddha@intel.com>
+ * Fenghua Yu <fenghua.yu@intel.com>
+ * Copyright (C) 1999 VA Linux Systems
+ * Copyright (C) 1999 Walt Drummond <drummond@valinux.com>
+ */
+/*
+ * ia64_switch_to now places correct virtual mapping in in TR2 for
+ * kernel stack. This allows us to handle interrupts without changing
+ * to physical mode.
+ *
+ * Jonathan Nicklin <nicklin@missioncriticallinux.com>
+ * Patrick O'Rourke <orourke@missioncriticallinux.com>
+ * 11/07/2000
+ */
+/*
+ * Copyright (c) 2008 Isaku Yamahata <yamahata at valinux co jp>
+ * VA Linux Systems Japan K.K.
+ * pv_ops.
+ */
+/*
+ * Global (preserved) predicate usage on syscall entry/exit path:
+ *
+ * pKStk: See entry.h.
+ * pUStk: See entry.h.
+ * pSys: See entry.h.
+ * pNonSys: !pSys
+ */
+
+
+#include <linux/pgtable.h>
+#include <asm/asmmacro.h>
+#include <asm/cache.h>
+#include <asm/errno.h>
+#include <asm/kregs.h>
+#include <asm/asm-offsets.h>
+#include <asm/percpu.h>
+#include <asm/processor.h>
+#include <asm/thread_info.h>
+#include <asm/unistd.h>
+#include <asm/ftrace.h>
+#include <asm/export.h>
+
+#include "minstate.h"
+
+ /*
+ * execve() is special because in case of success, we need to
+ * setup a null register window frame.
+ */
+ENTRY(ia64_execve)
+ /*
+ * Allocate 8 input registers since ptrace() may clobber them
+ */
+ .prologue ASM_UNW_PRLG_RP|ASM_UNW_PRLG_PFS, ASM_UNW_PRLG_GRSAVE(8)
+ alloc loc1=ar.pfs,8,2,3,0
+ mov loc0=rp
+ .body
+ mov out0=in0 // filename
+ ;; // stop bit between alloc and call
+ mov out1=in1 // argv
+ mov out2=in2 // envp
+ br.call.sptk.many rp=sys_execve
+.ret0:
+ cmp4.ge p6,p7=r8,r0
+ mov ar.pfs=loc1 // restore ar.pfs
+ sxt4 r8=r8 // return 64-bit result
+ ;;
+ stf.spill [sp]=f0
+ mov rp=loc0
+(p6) mov ar.pfs=r0 // clear ar.pfs on success
+(p7) br.ret.sptk.many rp
+
+ /*
+ * In theory, we'd have to zap this state only to prevent leaking of
+ * security sensitive state (e.g., if current->mm->dumpable is zero). However,
+ * this executes in less than 20 cycles even on Itanium, so it's not worth
+ * optimizing for...).
+ */
+ mov ar.unat=0; mov ar.lc=0
+ mov r4=0; mov f2=f0; mov b1=r0
+ mov r5=0; mov f3=f0; mov b2=r0
+ mov r6=0; mov f4=f0; mov b3=r0
+ mov r7=0; mov f5=f0; mov b4=r0
+ ldf.fill f12=[sp]; mov f13=f0; mov b5=r0
+ ldf.fill f14=[sp]; ldf.fill f15=[sp]; mov f16=f0
+ ldf.fill f17=[sp]; ldf.fill f18=[sp]; mov f19=f0
+ ldf.fill f20=[sp]; ldf.fill f21=[sp]; mov f22=f0
+ ldf.fill f23=[sp]; ldf.fill f24=[sp]; mov f25=f0
+ ldf.fill f26=[sp]; ldf.fill f27=[sp]; mov f28=f0
+ ldf.fill f29=[sp]; ldf.fill f30=[sp]; mov f31=f0
+ br.ret.sptk.many rp
+END(ia64_execve)
+
+/*
+ * sys_clone2(u64 flags, u64 ustack_base, u64 ustack_size, u64 parent_tidptr, u64 child_tidptr,
+ * u64 tls)
+ */
+GLOBAL_ENTRY(sys_clone2)
+ /*
+ * Allocate 8 input registers since ptrace() may clobber them
+ */
+ .prologue ASM_UNW_PRLG_RP|ASM_UNW_PRLG_PFS, ASM_UNW_PRLG_GRSAVE(8)
+ alloc r16=ar.pfs,8,2,6,0
+ DO_SAVE_SWITCH_STACK
+ mov loc0=rp
+ mov loc1=r16 // save ar.pfs across ia64_clone
+ .body
+ mov out0=in0
+ mov out1=in1
+ mov out2=in2
+ mov out3=in3
+ mov out4=in4
+ mov out5=in5
+ br.call.sptk.many rp=ia64_clone
+.ret1: .restore sp
+ adds sp=IA64_SWITCH_STACK_SIZE,sp // pop the switch stack
+ mov ar.pfs=loc1
+ mov rp=loc0
+ br.ret.sptk.many rp
+END(sys_clone2)
+
+/*
+ * sys_clone(u64 flags, u64 ustack_base, u64 parent_tidptr, u64 child_tidptr, u64 tls)
+ * Deprecated. Use sys_clone2() instead.
+ */
+GLOBAL_ENTRY(sys_clone)
+ /*
+ * Allocate 8 input registers since ptrace() may clobber them
+ */
+ .prologue ASM_UNW_PRLG_RP|ASM_UNW_PRLG_PFS, ASM_UNW_PRLG_GRSAVE(8)
+ alloc r16=ar.pfs,8,2,6,0
+ DO_SAVE_SWITCH_STACK
+ mov loc0=rp
+ mov loc1=r16 // save ar.pfs across ia64_clone
+ .body
+ mov out0=in0
+ mov out1=in1
+ mov out2=16 // stacksize (compensates for 16-byte scratch area)
+ mov out3=in3
+ mov out4=in4
+ mov out5=in5
+ br.call.sptk.many rp=ia64_clone
+.ret2: .restore sp
+ adds sp=IA64_SWITCH_STACK_SIZE,sp // pop the switch stack
+ mov ar.pfs=loc1
+ mov rp=loc0
+ br.ret.sptk.many rp
+END(sys_clone)
+
+/*
+ * prev_task <- ia64_switch_to(struct task_struct *next)
+ * With Ingo's new scheduler, interrupts are disabled when this routine gets
+ * called. The code starting at .map relies on this. The rest of the code
+ * doesn't care about the interrupt masking status.
+ */
+GLOBAL_ENTRY(ia64_switch_to)
+ .prologue
+ alloc r16=ar.pfs,1,0,0,0
+ DO_SAVE_SWITCH_STACK
+ .body
+
+ adds r22=IA64_TASK_THREAD_KSP_OFFSET,r13
+ movl r25=init_task
+ mov r27=IA64_KR(CURRENT_STACK)
+ adds r21=IA64_TASK_THREAD_KSP_OFFSET,in0
+ dep r20=0,in0,61,3 // physical address of "next"
+ ;;
+ st8 [r22]=sp // save kernel stack pointer of old task
+ shr.u r26=r20,IA64_GRANULE_SHIFT
+ cmp.eq p7,p6=r25,in0
+ ;;
+ /*
+ * If we've already mapped this task's page, we can skip doing it again.
+ */
+(p6) cmp.eq p7,p6=r26,r27
+(p6) br.cond.dpnt .map
+ ;;
+.done:
+ ld8 sp=[r21] // load kernel stack pointer of new task
+ MOV_TO_KR(CURRENT, in0, r8, r9) // update "current" application register
+ mov r8=r13 // return pointer to previously running task
+ mov r13=in0 // set "current" pointer
+ ;;
+ DO_LOAD_SWITCH_STACK
+
+#ifdef CONFIG_SMP
+ sync.i // ensure "fc"s done by this CPU are visible on other CPUs
+#endif
+ br.ret.sptk.many rp // boogie on out in new context
+
+.map:
+ RSM_PSR_IC(r25) // interrupts (psr.i) are already disabled here
+ movl r25=PAGE_KERNEL
+ ;;
+ srlz.d
+ or r23=r25,r20 // construct PA | page properties
+ mov r25=IA64_GRANULE_SHIFT<<2
+ ;;
+ MOV_TO_ITIR(p0, r25, r8)
+ MOV_TO_IFA(in0, r8) // VA of next task...
+ ;;
+ mov r25=IA64_TR_CURRENT_STACK
+ MOV_TO_KR(CURRENT_STACK, r26, r8, r9) // remember last page we mapped...
+ ;;
+ itr.d dtr[r25]=r23 // wire in new mapping...
+ SSM_PSR_IC_AND_SRLZ_D(r8, r9) // reenable the psr.ic bit
+ br.cond.sptk .done
+END(ia64_switch_to)
+
+/*
+ * Note that interrupts are enabled during save_switch_stack and load_switch_stack. This
+ * means that we may get an interrupt with "sp" pointing to the new kernel stack while
+ * ar.bspstore is still pointing to the old kernel backing store area. Since ar.rsc,
+ * ar.rnat, ar.bsp, and ar.bspstore are all preserved by interrupts, this is not a
+ * problem. Also, we don't need to specify unwind information for preserved registers
+ * that are not modified in save_switch_stack as the right unwind information is already
+ * specified at the call-site of save_switch_stack.
+ */
+
+/*
+ * save_switch_stack:
+ * - r16 holds ar.pfs
+ * - b7 holds address to return to
+ * - rp (b0) holds return address to save
+ */
+GLOBAL_ENTRY(save_switch_stack)
+ .prologue
+ .altrp b7
+ flushrs // flush dirty regs to backing store (must be first in insn group)
+ .save @priunat,r17
+ mov r17=ar.unat // preserve caller's
+ .body
+#ifdef CONFIG_ITANIUM
+ adds r2=16+128,sp
+ adds r3=16+64,sp
+ adds r14=SW(R4)+16,sp
+ ;;
+ st8.spill [r14]=r4,16 // spill r4
+ lfetch.fault.excl.nt1 [r3],128
+ ;;
+ lfetch.fault.excl.nt1 [r2],128
+ lfetch.fault.excl.nt1 [r3],128
+ ;;
+ lfetch.fault.excl [r2]
+ lfetch.fault.excl [r3]
+ adds r15=SW(R5)+16,sp
+#else
+ add r2=16+3*128,sp
+ add r3=16,sp
+ add r14=SW(R4)+16,sp
+ ;;
+ st8.spill [r14]=r4,SW(R6)-SW(R4) // spill r4 and prefetch offset 0x1c0
+ lfetch.fault.excl.nt1 [r3],128 // prefetch offset 0x010
+ ;;
+ lfetch.fault.excl.nt1 [r3],128 // prefetch offset 0x090
+ lfetch.fault.excl.nt1 [r2],128 // prefetch offset 0x190
+ ;;
+ lfetch.fault.excl.nt1 [r3] // prefetch offset 0x110
+ lfetch.fault.excl.nt1 [r2] // prefetch offset 0x210
+ adds r15=SW(R5)+16,sp
+#endif
+ ;;
+ st8.spill [r15]=r5,SW(R7)-SW(R5) // spill r5
+ mov.m ar.rsc=0 // put RSE in mode: enforced lazy, little endian, pl 0
+ add r2=SW(F2)+16,sp // r2 = &sw->f2
+ ;;
+ st8.spill [r14]=r6,SW(B0)-SW(R6) // spill r6
+ mov.m r18=ar.fpsr // preserve fpsr
+ add r3=SW(F3)+16,sp // r3 = &sw->f3
+ ;;
+ stf.spill [r2]=f2,32
+ mov.m r19=ar.rnat
+ mov r21=b0
+
+ stf.spill [r3]=f3,32
+ st8.spill [r15]=r7,SW(B2)-SW(R7) // spill r7
+ mov r22=b1
+ ;;
+ // since we're done with the spills, read and save ar.unat:
+ mov.m r29=ar.unat
+ mov.m r20=ar.bspstore
+ mov r23=b2
+ stf.spill [r2]=f4,32
+ stf.spill [r3]=f5,32
+ mov r24=b3
+ ;;
+ st8 [r14]=r21,SW(B1)-SW(B0) // save b0
+ st8 [r15]=r23,SW(B3)-SW(B2) // save b2
+ mov r25=b4
+ mov r26=b5
+ ;;
+ st8 [r14]=r22,SW(B4)-SW(B1) // save b1
+ st8 [r15]=r24,SW(AR_PFS)-SW(B3) // save b3
+ mov r21=ar.lc // I-unit
+ stf.spill [r2]=f12,32
+ stf.spill [r3]=f13,32
+ ;;
+ st8 [r14]=r25,SW(B5)-SW(B4) // save b4
+ st8 [r15]=r16,SW(AR_LC)-SW(AR_PFS) // save ar.pfs
+ stf.spill [r2]=f14,32
+ stf.spill [r3]=f15,32
+ ;;
+ st8 [r14]=r26 // save b5
+ st8 [r15]=r21 // save ar.lc
+ stf.spill [r2]=f16,32
+ stf.spill [r3]=f17,32
+ ;;
+ stf.spill [r2]=f18,32
+ stf.spill [r3]=f19,32
+ ;;
+ stf.spill [r2]=f20,32
+ stf.spill [r3]=f21,32
+ ;;
+ stf.spill [r2]=f22,32
+ stf.spill [r3]=f23,32
+ ;;
+ stf.spill [r2]=f24,32
+ stf.spill [r3]=f25,32
+ ;;
+ stf.spill [r2]=f26,32
+ stf.spill [r3]=f27,32
+ ;;
+ stf.spill [r2]=f28,32
+ stf.spill [r3]=f29,32
+ ;;
+ stf.spill [r2]=f30,SW(AR_UNAT)-SW(F30)
+ stf.spill [r3]=f31,SW(PR)-SW(F31)
+ add r14=SW(CALLER_UNAT)+16,sp
+ ;;
+ st8 [r2]=r29,SW(AR_RNAT)-SW(AR_UNAT) // save ar.unat
+ st8 [r14]=r17,SW(AR_FPSR)-SW(CALLER_UNAT) // save caller_unat
+ mov r21=pr
+ ;;
+ st8 [r2]=r19,SW(AR_BSPSTORE)-SW(AR_RNAT) // save ar.rnat
+ st8 [r3]=r21 // save predicate registers
+ ;;
+ st8 [r2]=r20 // save ar.bspstore
+ st8 [r14]=r18 // save fpsr
+ mov ar.rsc=3 // put RSE back into eager mode, pl 0
+ br.cond.sptk.many b7
+END(save_switch_stack)
+
+/*
+ * load_switch_stack:
+ * - "invala" MUST be done at call site (normally in DO_LOAD_SWITCH_STACK)
+ * - b7 holds address to return to
+ * - must not touch r8-r11
+ */
+GLOBAL_ENTRY(load_switch_stack)
+ .prologue
+ .altrp b7
+
+ .body
+ lfetch.fault.nt1 [sp]
+ adds r2=SW(AR_BSPSTORE)+16,sp
+ adds r3=SW(AR_UNAT)+16,sp
+ mov ar.rsc=0 // put RSE into enforced lazy mode
+ adds r14=SW(CALLER_UNAT)+16,sp
+ adds r15=SW(AR_FPSR)+16,sp
+ ;;
+ ld8 r27=[r2],(SW(B0)-SW(AR_BSPSTORE)) // bspstore
+ ld8 r29=[r3],(SW(B1)-SW(AR_UNAT)) // unat
+ ;;
+ ld8 r21=[r2],16 // restore b0
+ ld8 r22=[r3],16 // restore b1
+ ;;
+ ld8 r23=[r2],16 // restore b2
+ ld8 r24=[r3],16 // restore b3
+ ;;
+ ld8 r25=[r2],16 // restore b4
+ ld8 r26=[r3],16 // restore b5
+ ;;
+ ld8 r16=[r2],(SW(PR)-SW(AR_PFS)) // ar.pfs
+ ld8 r17=[r3],(SW(AR_RNAT)-SW(AR_LC)) // ar.lc
+ ;;
+ ld8 r28=[r2] // restore pr
+ ld8 r30=[r3] // restore rnat
+ ;;
+ ld8 r18=[r14],16 // restore caller's unat
+ ld8 r19=[r15],24 // restore fpsr
+ ;;
+ ldf.fill f2=[r14],32
+ ldf.fill f3=[r15],32
+ ;;
+ ldf.fill f4=[r14],32
+ ldf.fill f5=[r15],32
+ ;;
+ ldf.fill f12=[r14],32
+ ldf.fill f13=[r15],32
+ ;;
+ ldf.fill f14=[r14],32
+ ldf.fill f15=[r15],32
+ ;;
+ ldf.fill f16=[r14],32
+ ldf.fill f17=[r15],32
+ ;;
+ ldf.fill f18=[r14],32
+ ldf.fill f19=[r15],32
+ mov b0=r21
+ ;;
+ ldf.fill f20=[r14],32
+ ldf.fill f21=[r15],32
+ mov b1=r22
+ ;;
+ ldf.fill f22=[r14],32
+ ldf.fill f23=[r15],32
+ mov b2=r23
+ ;;
+ mov ar.bspstore=r27
+ mov ar.unat=r29 // establish unat holding the NaT bits for r4-r7
+ mov b3=r24
+ ;;
+ ldf.fill f24=[r14],32
+ ldf.fill f25=[r15],32
+ mov b4=r25
+ ;;
+ ldf.fill f26=[r14],32
+ ldf.fill f27=[r15],32
+ mov b5=r26
+ ;;
+ ldf.fill f28=[r14],32
+ ldf.fill f29=[r15],32
+ mov ar.pfs=r16
+ ;;
+ ldf.fill f30=[r14],32
+ ldf.fill f31=[r15],24
+ mov ar.lc=r17
+ ;;
+ ld8.fill r4=[r14],16
+ ld8.fill r5=[r15],16
+ mov pr=r28,-1
+ ;;
+ ld8.fill r6=[r14],16
+ ld8.fill r7=[r15],16
+
+ mov ar.unat=r18 // restore caller's unat
+ mov ar.rnat=r30 // must restore after bspstore but before rsc!
+ mov ar.fpsr=r19 // restore fpsr
+ mov ar.rsc=3 // put RSE back into eager mode, pl 0
+ br.cond.sptk.many b7
+END(load_switch_stack)
+
+ /*
+ * Invoke a system call, but do some tracing before and after the call.
+ * We MUST preserve the current register frame throughout this routine
+ * because some system calls (such as ia64_execve) directly
+ * manipulate ar.pfs.
+ */
+GLOBAL_ENTRY(ia64_trace_syscall)
+ PT_REGS_UNWIND_INFO(0)
+ /*
+ * We need to preserve the scratch registers f6-f11 in case the system
+ * call is sigreturn.
+ */
+ adds r16=PT(F6)+16,sp
+ adds r17=PT(F7)+16,sp
+ ;;
+ stf.spill [r16]=f6,32
+ stf.spill [r17]=f7,32
+ ;;
+ stf.spill [r16]=f8,32
+ stf.spill [r17]=f9,32
+ ;;
+ stf.spill [r16]=f10
+ stf.spill [r17]=f11
+ br.call.sptk.many rp=syscall_trace_enter // give parent a chance to catch syscall args
+ cmp.lt p6,p0=r8,r0 // check tracehook
+ adds r2=PT(R8)+16,sp // r2 = &pt_regs.r8
+ adds r3=PT(R10)+16,sp // r3 = &pt_regs.r10
+ mov r10=0
+(p6) br.cond.sptk strace_error // syscall failed ->
+ adds r16=PT(F6)+16,sp
+ adds r17=PT(F7)+16,sp
+ ;;
+ ldf.fill f6=[r16],32
+ ldf.fill f7=[r17],32
+ ;;
+ ldf.fill f8=[r16],32
+ ldf.fill f9=[r17],32
+ ;;
+ ldf.fill f10=[r16]
+ ldf.fill f11=[r17]
+ // the syscall number may have changed, so re-load it and re-calculate the
+ // syscall entry-point:
+ adds r15=PT(R15)+16,sp // r15 = &pt_regs.r15 (syscall #)
+ ;;
+ ld8 r15=[r15]
+ mov r3=NR_syscalls - 1
+ ;;
+ adds r15=-1024,r15
+ movl r16=sys_call_table
+ ;;
+ shladd r20=r15,3,r16 // r20 = sys_call_table + 8*(syscall-1024)
+ cmp.leu p6,p7=r15,r3
+ ;;
+(p6) ld8 r20=[r20] // load address of syscall entry point
+(p7) movl r20=sys_ni_syscall
+ ;;
+ mov b6=r20
+ br.call.sptk.many rp=b6 // do the syscall
+.strace_check_retval:
+ cmp.lt p6,p0=r8,r0 // syscall failed?
+ adds r2=PT(R8)+16,sp // r2 = &pt_regs.r8
+ adds r3=PT(R10)+16,sp // r3 = &pt_regs.r10
+ mov r10=0
+(p6) br.cond.sptk strace_error // syscall failed ->
+ ;; // avoid RAW on r10
+.strace_save_retval:
+.mem.offset 0,0; st8.spill [r2]=r8 // store return value in slot for r8
+.mem.offset 8,0; st8.spill [r3]=r10 // clear error indication in slot for r10
+ br.call.sptk.many rp=syscall_trace_leave // give parent a chance to catch return value
+.ret3:
+(pUStk) cmp.eq.unc p6,p0=r0,r0 // p6 <- pUStk
+(pUStk) rsm psr.i // disable interrupts
+ br.cond.sptk ia64_work_pending_syscall_end
+
+strace_error:
+ ld8 r3=[r2] // load pt_regs.r8
+ sub r9=0,r8 // negate return value to get errno value
+ ;;
+ cmp.ne p6,p0=r3,r0 // is pt_regs.r8!=0?
+ adds r3=16,r2 // r3=&pt_regs.r10
+ ;;
+(p6) mov r10=-1
+(p6) mov r8=r9
+ br.cond.sptk .strace_save_retval
+END(ia64_trace_syscall)
+
+ /*
+ * When traced and returning from sigreturn, we invoke syscall_trace but then
+ * go straight to ia64_leave_kernel rather than ia64_leave_syscall.
+ */
+GLOBAL_ENTRY(ia64_strace_leave_kernel)
+ PT_REGS_UNWIND_INFO(0)
+{ /*
+ * Some versions of gas generate bad unwind info if the first instruction of a
+ * procedure doesn't go into the first slot of a bundle. This is a workaround.
+ */
+ nop.m 0
+ nop.i 0
+ br.call.sptk.many rp=syscall_trace_leave // give parent a chance to catch return value
+}
+.ret4: br.cond.sptk ia64_leave_kernel
+END(ia64_strace_leave_kernel)
+
+ENTRY(call_payload)
+ .prologue ASM_UNW_PRLG_RP|ASM_UNW_PRLG_PFS, ASM_UNW_PRLG_GRSAVE(0)
+ /* call the kernel_thread payload; fn is in r4, arg - in r5 */
+ alloc loc1=ar.pfs,0,3,1,0
+ mov loc0=rp
+ mov loc2=gp
+ mov out0=r5 // arg
+ ld8 r14 = [r4], 8 // fn.address
+ ;;
+ mov b6 = r14
+ ld8 gp = [r4] // fn.gp
+ ;;
+ br.call.sptk.many rp=b6 // fn(arg)
+.ret12: mov gp=loc2
+ mov rp=loc0
+ mov ar.pfs=loc1
+ /* ... and if it has returned, we are going to userland */
+ cmp.ne pKStk,pUStk=r0,r0
+ br.ret.sptk.many rp
+END(call_payload)
+
+GLOBAL_ENTRY(ia64_ret_from_clone)
+ PT_REGS_UNWIND_INFO(0)
+{ /*
+ * Some versions of gas generate bad unwind info if the first instruction of a
+ * procedure doesn't go into the first slot of a bundle. This is a workaround.
+ */
+ nop.m 0
+ nop.i 0
+ /*
+ * We need to call schedule_tail() to complete the scheduling process.
+ * Called by ia64_switch_to() after ia64_clone()->copy_thread(). r8 contains the
+ * address of the previously executing task.
+ */
+ br.call.sptk.many rp=ia64_invoke_schedule_tail
+}
+.ret8:
+(pKStk) br.call.sptk.many rp=call_payload
+ adds r2=TI_FLAGS+IA64_TASK_SIZE,r13
+ ;;
+ ld4 r2=[r2]
+ ;;
+ mov r8=0
+ and r2=_TIF_SYSCALL_TRACEAUDIT,r2
+ ;;
+ cmp.ne p6,p0=r2,r0
+(p6) br.cond.spnt .strace_check_retval
+ ;; // added stop bits to prevent r8 dependency
+END(ia64_ret_from_clone)
+ // fall through
+GLOBAL_ENTRY(ia64_ret_from_syscall)
+ PT_REGS_UNWIND_INFO(0)
+ cmp.ge p6,p7=r8,r0 // syscall executed successfully?
+ adds r2=PT(R8)+16,sp // r2 = &pt_regs.r8
+ mov r10=r0 // clear error indication in r10
+(p7) br.cond.spnt handle_syscall_error // handle potential syscall failure
+END(ia64_ret_from_syscall)
+ // fall through
+
+/*
+ * ia64_leave_syscall(): Same as ia64_leave_kernel, except that it doesn't
+ * need to switch to bank 0 and doesn't restore the scratch registers.
+ * To avoid leaking kernel bits, the scratch registers are set to
+ * the following known-to-be-safe values:
+ *
+ * r1: restored (global pointer)
+ * r2: cleared
+ * r3: 1 (when returning to user-level)
+ * r8-r11: restored (syscall return value(s))
+ * r12: restored (user-level stack pointer)
+ * r13: restored (user-level thread pointer)
+ * r14: set to __kernel_syscall_via_epc
+ * r15: restored (syscall #)
+ * r16-r17: cleared
+ * r18: user-level b6
+ * r19: cleared
+ * r20: user-level ar.fpsr
+ * r21: user-level b0
+ * r22: cleared
+ * r23: user-level ar.bspstore
+ * r24: user-level ar.rnat
+ * r25: user-level ar.unat
+ * r26: user-level ar.pfs
+ * r27: user-level ar.rsc
+ * r28: user-level ip
+ * r29: user-level psr
+ * r30: user-level cfm
+ * r31: user-level pr
+ * f6-f11: cleared
+ * pr: restored (user-level pr)
+ * b0: restored (user-level rp)
+ * b6: restored
+ * b7: set to __kernel_syscall_via_epc
+ * ar.unat: restored (user-level ar.unat)
+ * ar.pfs: restored (user-level ar.pfs)
+ * ar.rsc: restored (user-level ar.rsc)
+ * ar.rnat: restored (user-level ar.rnat)
+ * ar.bspstore: restored (user-level ar.bspstore)
+ * ar.fpsr: restored (user-level ar.fpsr)
+ * ar.ccv: cleared
+ * ar.csd: cleared
+ * ar.ssd: cleared
+ */
+GLOBAL_ENTRY(ia64_leave_syscall)
+ PT_REGS_UNWIND_INFO(0)
+ /*
+ * work.need_resched etc. mustn't get changed by this CPU before it returns to
+ * user- or fsys-mode, hence we disable interrupts early on.
+ *
+ * p6 controls whether current_thread_info()->flags needs to be check for
+ * extra work. We always check for extra work when returning to user-level.
+ * With CONFIG_PREEMPTION, we also check for extra work when the preempt_count
+ * is 0. After extra work processing has been completed, execution
+ * resumes at ia64_work_processed_syscall with p6 set to 1 if the extra-work-check
+ * needs to be redone.
+ */
+#ifdef CONFIG_PREEMPTION
+ RSM_PSR_I(p0, r2, r18) // disable interrupts
+ cmp.eq pLvSys,p0=r0,r0 // pLvSys=1: leave from syscall
+(pKStk) adds r20=TI_PRE_COUNT+IA64_TASK_SIZE,r13
+ ;;
+ .pred.rel.mutex pUStk,pKStk
+(pKStk) ld4 r21=[r20] // r21 <- preempt_count
+(pUStk) mov r21=0 // r21 <- 0
+ ;;
+ cmp.eq p6,p0=r21,r0 // p6 <- pUStk || (preempt_count == 0)
+#else /* !CONFIG_PREEMPTION */
+ RSM_PSR_I(pUStk, r2, r18)
+ cmp.eq pLvSys,p0=r0,r0 // pLvSys=1: leave from syscall
+(pUStk) cmp.eq.unc p6,p0=r0,r0 // p6 <- pUStk
+#endif
+.global ia64_work_processed_syscall;
+ia64_work_processed_syscall:
+#ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
+ adds r2=PT(LOADRS)+16,r12
+ MOV_FROM_ITC(pUStk, p9, r22, r19) // fetch time at leave
+ adds r18=TI_FLAGS+IA64_TASK_SIZE,r13
+ ;;
+(p6) ld4 r31=[r18] // load current_thread_info()->flags
+ ld8 r19=[r2],PT(B6)-PT(LOADRS) // load ar.rsc value for "loadrs"
+ adds r3=PT(AR_BSPSTORE)+16,r12 // deferred
+ ;;
+#else
+ adds r2=PT(LOADRS)+16,r12
+ adds r3=PT(AR_BSPSTORE)+16,r12
+ adds r18=TI_FLAGS+IA64_TASK_SIZE,r13
+ ;;
+(p6) ld4 r31=[r18] // load current_thread_info()->flags
+ ld8 r19=[r2],PT(B6)-PT(LOADRS) // load ar.rsc value for "loadrs"
+ nop.i 0
+ ;;
+#endif
+ mov r16=ar.bsp // M2 get existing backing store pointer
+ ld8 r18=[r2],PT(R9)-PT(B6) // load b6
+(p6) and r15=TIF_WORK_MASK,r31 // any work other than TIF_SYSCALL_TRACE?
+ ;;
+ ld8 r23=[r3],PT(R11)-PT(AR_BSPSTORE) // load ar.bspstore (may be garbage)
+(p6) cmp4.ne.unc p6,p0=r15, r0 // any special work pending?
+(p6) br.cond.spnt .work_pending_syscall
+ ;;
+ // start restoring the state saved on the kernel stack (struct pt_regs):
+ ld8 r9=[r2],PT(CR_IPSR)-PT(R9)
+ ld8 r11=[r3],PT(CR_IIP)-PT(R11)
+(pNonSys) break 0 // bug check: we shouldn't be here if pNonSys is TRUE!
+ ;;
+ invala // M0|1 invalidate ALAT
+ RSM_PSR_I_IC(r28, r29, r30) // M2 turn off interrupts and interruption collection
+ cmp.eq p9,p0=r0,r0 // A set p9 to indicate that we should restore cr.ifs
+
+ ld8 r29=[r2],16 // M0|1 load cr.ipsr
+ ld8 r28=[r3],16 // M0|1 load cr.iip
+#ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
+(pUStk) add r14=TI_AC_LEAVE+IA64_TASK_SIZE,r13
+ ;;
+ ld8 r30=[r2],16 // M0|1 load cr.ifs
+ ld8 r25=[r3],16 // M0|1 load ar.unat
+(pUStk) add r15=IA64_TASK_THREAD_ON_USTACK_OFFSET,r13
+ ;;
+#else
+ mov r22=r0 // A clear r22
+ ;;
+ ld8 r30=[r2],16 // M0|1 load cr.ifs
+ ld8 r25=[r3],16 // M0|1 load ar.unat
+(pUStk) add r14=IA64_TASK_THREAD_ON_USTACK_OFFSET,r13
+ ;;
+#endif
+ ld8 r26=[r2],PT(B0)-PT(AR_PFS) // M0|1 load ar.pfs
+ MOV_FROM_PSR(pKStk, r22, r21) // M2 read PSR now that interrupts are disabled
+ nop 0
+ ;;
+ ld8 r21=[r2],PT(AR_RNAT)-PT(B0) // M0|1 load b0
+ ld8 r27=[r3],PT(PR)-PT(AR_RSC) // M0|1 load ar.rsc
+ mov f6=f0 // F clear f6
+ ;;
+ ld8 r24=[r2],PT(AR_FPSR)-PT(AR_RNAT) // M0|1 load ar.rnat (may be garbage)
+ ld8 r31=[r3],PT(R1)-PT(PR) // M0|1 load predicates
+ mov f7=f0 // F clear f7
+ ;;
+ ld8 r20=[r2],PT(R12)-PT(AR_FPSR) // M0|1 load ar.fpsr
+ ld8.fill r1=[r3],16 // M0|1 load r1
+(pUStk) mov r17=1 // A
+ ;;
+#ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
+(pUStk) st1 [r15]=r17 // M2|3
+#else
+(pUStk) st1 [r14]=r17 // M2|3
+#endif
+ ld8.fill r13=[r3],16 // M0|1
+ mov f8=f0 // F clear f8
+ ;;
+ ld8.fill r12=[r2] // M0|1 restore r12 (sp)
+ ld8.fill r15=[r3] // M0|1 restore r15
+ mov b6=r18 // I0 restore b6
+
+ LOAD_PHYS_STACK_REG_SIZE(r17)
+ mov f9=f0 // F clear f9
+(pKStk) br.cond.dpnt.many skip_rbs_switch // B
+
+ srlz.d // M0 ensure interruption collection is off (for cover)
+ shr.u r18=r19,16 // I0|1 get byte size of existing "dirty" partition
+ COVER // B add current frame into dirty partition & set cr.ifs
+ ;;
+#ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
+ mov r19=ar.bsp // M2 get new backing store pointer
+ st8 [r14]=r22 // M save time at leave
+ mov f10=f0 // F clear f10
+
+ mov r22=r0 // A clear r22
+ movl r14=__kernel_syscall_via_epc // X
+ ;;
+#else
+ mov r19=ar.bsp // M2 get new backing store pointer
+ mov f10=f0 // F clear f10
+
+ nop.m 0
+ movl r14=__kernel_syscall_via_epc // X
+ ;;
+#endif
+ mov.m ar.csd=r0 // M2 clear ar.csd
+ mov.m ar.ccv=r0 // M2 clear ar.ccv
+ mov b7=r14 // I0 clear b7 (hint with __kernel_syscall_via_epc)
+
+ mov.m ar.ssd=r0 // M2 clear ar.ssd
+ mov f11=f0 // F clear f11
+ br.cond.sptk.many rbs_switch // B
+END(ia64_leave_syscall)
+
+GLOBAL_ENTRY(ia64_leave_kernel)
+ PT_REGS_UNWIND_INFO(0)
+ /*
+ * work.need_resched etc. mustn't get changed by this CPU before it returns to
+ * user- or fsys-mode, hence we disable interrupts early on.
+ *
+ * p6 controls whether current_thread_info()->flags needs to be check for
+ * extra work. We always check for extra work when returning to user-level.
+ * With CONFIG_PREEMPTION, we also check for extra work when the preempt_count
+ * is 0. After extra work processing has been completed, execution
+ * resumes at .work_processed_syscall with p6 set to 1 if the extra-work-check
+ * needs to be redone.
+ */
+#ifdef CONFIG_PREEMPTION
+ RSM_PSR_I(p0, r17, r31) // disable interrupts
+ cmp.eq p0,pLvSys=r0,r0 // pLvSys=0: leave from kernel
+(pKStk) adds r20=TI_PRE_COUNT+IA64_TASK_SIZE,r13
+ ;;
+ .pred.rel.mutex pUStk,pKStk
+(pKStk) ld4 r21=[r20] // r21 <- preempt_count
+(pUStk) mov r21=0 // r21 <- 0
+ ;;
+ cmp.eq p6,p0=r21,r0 // p6 <- pUStk || (preempt_count == 0)
+#else
+ RSM_PSR_I(pUStk, r17, r31)
+ cmp.eq p0,pLvSys=r0,r0 // pLvSys=0: leave from kernel
+(pUStk) cmp.eq.unc p6,p0=r0,r0 // p6 <- pUStk
+#endif
+.work_processed_kernel:
+ adds r17=TI_FLAGS+IA64_TASK_SIZE,r13
+ ;;
+(p6) ld4 r31=[r17] // load current_thread_info()->flags
+ adds r21=PT(PR)+16,r12
+ ;;
+
+ lfetch [r21],PT(CR_IPSR)-PT(PR)
+ adds r2=PT(B6)+16,r12
+ adds r3=PT(R16)+16,r12
+ ;;
+ lfetch [r21]
+ ld8 r28=[r2],8 // load b6
+ adds r29=PT(R24)+16,r12
+
+ ld8.fill r16=[r3],PT(AR_CSD)-PT(R16)
+ adds r30=PT(AR_CCV)+16,r12
+(p6) and r19=TIF_WORK_MASK,r31 // any work other than TIF_SYSCALL_TRACE?
+ ;;
+ ld8.fill r24=[r29]
+ ld8 r15=[r30] // load ar.ccv
+(p6) cmp4.ne.unc p6,p0=r19, r0 // any special work pending?
+ ;;
+ ld8 r29=[r2],16 // load b7
+ ld8 r30=[r3],16 // load ar.csd
+(p6) br.cond.spnt .work_pending
+ ;;
+ ld8 r31=[r2],16 // load ar.ssd
+ ld8.fill r8=[r3],16
+ ;;
+ ld8.fill r9=[r2],16
+ ld8.fill r10=[r3],PT(R17)-PT(R10)
+ ;;
+ ld8.fill r11=[r2],PT(R18)-PT(R11)
+ ld8.fill r17=[r3],16
+ ;;
+ ld8.fill r18=[r2],16
+ ld8.fill r19=[r3],16
+ ;;
+ ld8.fill r20=[r2],16
+ ld8.fill r21=[r3],16
+ mov ar.csd=r30
+ mov ar.ssd=r31
+ ;;
+ RSM_PSR_I_IC(r23, r22, r25) // initiate turning off of interrupt and interruption collection
+ invala // invalidate ALAT
+ ;;
+ ld8.fill r22=[r2],24
+ ld8.fill r23=[r3],24
+ mov b6=r28
+ ;;
+ ld8.fill r25=[r2],16
+ ld8.fill r26=[r3],16
+ mov b7=r29
+ ;;
+ ld8.fill r27=[r2],16
+ ld8.fill r28=[r3],16
+ ;;
+ ld8.fill r29=[r2],16
+ ld8.fill r30=[r3],24
+ ;;
+ ld8.fill r31=[r2],PT(F9)-PT(R31)
+ adds r3=PT(F10)-PT(F6),r3
+ ;;
+ ldf.fill f9=[r2],PT(F6)-PT(F9)
+ ldf.fill f10=[r3],PT(F8)-PT(F10)
+ ;;
+ ldf.fill f6=[r2],PT(F7)-PT(F6)
+ ;;
+ ldf.fill f7=[r2],PT(F11)-PT(F7)
+ ldf.fill f8=[r3],32
+ ;;
+ srlz.d // ensure that inter. collection is off (VHPT is don't care, since text is pinned)
+ mov ar.ccv=r15
+ ;;
+ ldf.fill f11=[r2]
+ BSW_0(r2, r3, r15) // switch back to bank 0 (no stop bit required beforehand...)
+ ;;
+(pUStk) mov r18=IA64_KR(CURRENT)// M2 (12 cycle read latency)
+ adds r16=PT(CR_IPSR)+16,r12
+ adds r17=PT(CR_IIP)+16,r12
+
+#ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
+ .pred.rel.mutex pUStk,pKStk
+ MOV_FROM_PSR(pKStk, r22, r29) // M2 read PSR now that interrupts are disabled
+ MOV_FROM_ITC(pUStk, p9, r22, r29) // M fetch time at leave
+ nop.i 0
+ ;;
+#else
+ MOV_FROM_PSR(pKStk, r22, r29) // M2 read PSR now that interrupts are disabled
+ nop.i 0
+ nop.i 0
+ ;;
+#endif
+ ld8 r29=[r16],16 // load cr.ipsr
+ ld8 r28=[r17],16 // load cr.iip
+ ;;
+ ld8 r30=[r16],16 // load cr.ifs
+ ld8 r25=[r17],16 // load ar.unat
+ ;;
+ ld8 r26=[r16],16 // load ar.pfs
+ ld8 r27=[r17],16 // load ar.rsc
+ cmp.eq p9,p0=r0,r0 // set p9 to indicate that we should restore cr.ifs
+ ;;
+ ld8 r24=[r16],16 // load ar.rnat (may be garbage)
+ ld8 r23=[r17],16 // load ar.bspstore (may be garbage)
+ ;;
+ ld8 r31=[r16],16 // load predicates
+ ld8 r21=[r17],16 // load b0
+ ;;
+ ld8 r19=[r16],16 // load ar.rsc value for "loadrs"
+ ld8.fill r1=[r17],16 // load r1
+ ;;
+ ld8.fill r12=[r16],16
+ ld8.fill r13=[r17],16
+#ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
+(pUStk) adds r3=TI_AC_LEAVE+IA64_TASK_SIZE,r18
+#else
+(pUStk) adds r18=IA64_TASK_THREAD_ON_USTACK_OFFSET,r18
+#endif
+ ;;
+ ld8 r20=[r16],16 // ar.fpsr
+ ld8.fill r15=[r17],16
+#ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
+(pUStk) adds r18=IA64_TASK_THREAD_ON_USTACK_OFFSET,r18 // deferred
+#endif
+ ;;
+ ld8.fill r14=[r16],16
+ ld8.fill r2=[r17]
+(pUStk) mov r17=1
+ ;;
+#ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
+ // mmi_ : ld8 st1 shr;; mmi_ : st8 st1 shr;;
+ // mib : mov add br -> mib : ld8 add br
+ // bbb_ : br nop cover;; mbb_ : mov br cover;;
+ //
+ // no one require bsp in r16 if (pKStk) branch is selected.
+(pUStk) st8 [r3]=r22 // save time at leave
+(pUStk) st1 [r18]=r17 // restore current->thread.on_ustack
+ shr.u r18=r19,16 // get byte size of existing "dirty" partition
+ ;;
+ ld8.fill r3=[r16] // deferred
+ LOAD_PHYS_STACK_REG_SIZE(r17)
+(pKStk) br.cond.dpnt skip_rbs_switch
+ mov r16=ar.bsp // get existing backing store pointer
+#else
+ ld8.fill r3=[r16]
+(pUStk) st1 [r18]=r17 // restore current->thread.on_ustack
+ shr.u r18=r19,16 // get byte size of existing "dirty" partition
+ ;;
+ mov r16=ar.bsp // get existing backing store pointer
+ LOAD_PHYS_STACK_REG_SIZE(r17)
+(pKStk) br.cond.dpnt skip_rbs_switch
+#endif
+
+ /*
+ * Restore user backing store.
+ *
+ * NOTE: alloc, loadrs, and cover can't be predicated.
+ */
+(pNonSys) br.cond.dpnt dont_preserve_current_frame
+ COVER // add current frame into dirty partition and set cr.ifs
+ ;;
+ mov r19=ar.bsp // get new backing store pointer
+rbs_switch:
+ sub r16=r16,r18 // krbs = old bsp - size of dirty partition
+ cmp.ne p9,p0=r0,r0 // clear p9 to skip restore of cr.ifs
+ ;;
+ sub r19=r19,r16 // calculate total byte size of dirty partition
+ add r18=64,r18 // don't force in0-in7 into memory...
+ ;;
+ shl r19=r19,16 // shift size of dirty partition into loadrs position
+ ;;
+dont_preserve_current_frame:
+ /*
+ * To prevent leaking bits between the kernel and user-space,
+ * we must clear the stacked registers in the "invalid" partition here.
+ * Not pretty, but at least it's fast (3.34 registers/cycle on Itanium,
+ * 5 registers/cycle on McKinley).
+ */
+# define pRecurse p6
+# define pReturn p7
+#ifdef CONFIG_ITANIUM
+# define Nregs 10
+#else
+# define Nregs 14
+#endif
+ alloc loc0=ar.pfs,2,Nregs-2,2,0
+ shr.u loc1=r18,9 // RNaTslots <= floor(dirtySize / (64*8))
+ sub r17=r17,r18 // r17 = (physStackedSize + 8) - dirtySize
+ ;;
+ mov ar.rsc=r19 // load ar.rsc to be used for "loadrs"
+ shladd in0=loc1,3,r17
+ mov in1=0
+ ;;
+ TEXT_ALIGN(32)
+rse_clear_invalid:
+#ifdef CONFIG_ITANIUM
+ // cycle 0
+ { .mii
+ alloc loc0=ar.pfs,2,Nregs-2,2,0
+ cmp.lt pRecurse,p0=Nregs*8,in0 // if more than Nregs regs left to clear, (re)curse
+ add out0=-Nregs*8,in0
+}{ .mfb
+ add out1=1,in1 // increment recursion count
+ nop.f 0
+ nop.b 0 // can't do br.call here because of alloc (WAW on CFM)
+ ;;
+}{ .mfi // cycle 1
+ mov loc1=0
+ nop.f 0
+ mov loc2=0
+}{ .mib
+ mov loc3=0
+ mov loc4=0
+(pRecurse) br.call.sptk.many b0=rse_clear_invalid
+
+}{ .mfi // cycle 2
+ mov loc5=0
+ nop.f 0
+ cmp.ne pReturn,p0=r0,in1 // if recursion count != 0, we need to do a br.ret
+}{ .mib
+ mov loc6=0
+ mov loc7=0
+(pReturn) br.ret.sptk.many b0
+}
+#else /* !CONFIG_ITANIUM */
+ alloc loc0=ar.pfs,2,Nregs-2,2,0
+ cmp.lt pRecurse,p0=Nregs*8,in0 // if more than Nregs regs left to clear, (re)curse
+ add out0=-Nregs*8,in0
+ add out1=1,in1 // increment recursion count
+ mov loc1=0
+ mov loc2=0
+ ;;
+ mov loc3=0
+ mov loc4=0
+ mov loc5=0
+ mov loc6=0
+ mov loc7=0
+(pRecurse) br.call.dptk.few b0=rse_clear_invalid
+ ;;
+ mov loc8=0
+ mov loc9=0
+ cmp.ne pReturn,p0=r0,in1 // if recursion count != 0, we need to do a br.ret
+ mov loc10=0
+ mov loc11=0
+(pReturn) br.ret.dptk.many b0
+#endif /* !CONFIG_ITANIUM */
+# undef pRecurse
+# undef pReturn
+ ;;
+ alloc r17=ar.pfs,0,0,0,0 // drop current register frame
+ ;;
+ loadrs
+ ;;
+skip_rbs_switch:
+ mov ar.unat=r25 // M2
+(pKStk) extr.u r22=r22,21,1 // I0 extract current value of psr.pp from r22
+(pLvSys)mov r19=r0 // A clear r19 for leave_syscall, no-op otherwise
+ ;;
+(pUStk) mov ar.bspstore=r23 // M2
+(pKStk) dep r29=r22,r29,21,1 // I0 update ipsr.pp with psr.pp
+(pLvSys)mov r16=r0 // A clear r16 for leave_syscall, no-op otherwise
+ ;;
+ MOV_TO_IPSR(p0, r29, r25) // M2
+ mov ar.pfs=r26 // I0
+(pLvSys)mov r17=r0 // A clear r17 for leave_syscall, no-op otherwise
+
+ MOV_TO_IFS(p9, r30, r25)// M2
+ mov b0=r21 // I0
+(pLvSys)mov r18=r0 // A clear r18 for leave_syscall, no-op otherwise
+
+ mov ar.fpsr=r20 // M2
+ MOV_TO_IIP(r28, r25) // M2
+ nop 0
+ ;;
+(pUStk) mov ar.rnat=r24 // M2 must happen with RSE in lazy mode
+ nop 0
+(pLvSys)mov r2=r0
+
+ mov ar.rsc=r27 // M2
+ mov pr=r31,-1 // I0
+ RFI // B
+
+ /*
+ * On entry:
+ * r20 = &current->thread_info->pre_count (if CONFIG_PREEMPTION)
+ * r31 = current->thread_info->flags
+ * On exit:
+ * p6 = TRUE if work-pending-check needs to be redone
+ *
+ * Interrupts are disabled on entry, reenabled depend on work, and
+ * disabled on exit.
+ */
+.work_pending_syscall:
+ add r2=-8,r2
+ add r3=-8,r3
+ ;;
+ st8 [r2]=r8
+ st8 [r3]=r10
+.work_pending:
+ tbit.z p6,p0=r31,TIF_NEED_RESCHED // is resched not needed?
+(p6) br.cond.sptk.few .notify
+ br.call.spnt.many rp=preempt_schedule_irq
+.ret9: cmp.eq p6,p0=r0,r0 // p6 <- 1 (re-check)
+(pLvSys)br.cond.sptk.few ia64_work_pending_syscall_end
+ br.cond.sptk.many .work_processed_kernel
+
+.notify:
+(pUStk) br.call.spnt.many rp=notify_resume_user
+.ret10: cmp.ne p6,p0=r0,r0 // p6 <- 0 (don't re-check)
+(pLvSys)br.cond.sptk.few ia64_work_pending_syscall_end
+ br.cond.sptk.many .work_processed_kernel
+
+.global ia64_work_pending_syscall_end;
+ia64_work_pending_syscall_end:
+ adds r2=PT(R8)+16,r12
+ adds r3=PT(R10)+16,r12
+ ;;
+ ld8 r8=[r2]
+ ld8 r10=[r3]
+ br.cond.sptk.many ia64_work_processed_syscall
+END(ia64_leave_kernel)
+
+ENTRY(handle_syscall_error)
+ /*
+ * Some system calls (e.g., ptrace, mmap) can return arbitrary values which could
+ * lead us to mistake a negative return value as a failed syscall. Those syscall
+ * must deposit a non-zero value in pt_regs.r8 to indicate an error. If
+ * pt_regs.r8 is zero, we assume that the call completed successfully.
+ */
+ PT_REGS_UNWIND_INFO(0)
+ ld8 r3=[r2] // load pt_regs.r8
+ ;;
+ cmp.eq p6,p7=r3,r0 // is pt_regs.r8==0?
+ ;;
+(p7) mov r10=-1
+(p7) sub r8=0,r8 // negate return value to get errno
+ br.cond.sptk ia64_leave_syscall
+END(handle_syscall_error)
+
+ /*
+ * Invoke schedule_tail(task) while preserving in0-in7, which may be needed
+ * in case a system call gets restarted.
+ */
+GLOBAL_ENTRY(ia64_invoke_schedule_tail)
+ .prologue ASM_UNW_PRLG_RP|ASM_UNW_PRLG_PFS, ASM_UNW_PRLG_GRSAVE(8)
+ alloc loc1=ar.pfs,8,2,1,0
+ mov loc0=rp
+ mov out0=r8 // Address of previous task
+ ;;
+ br.call.sptk.many rp=schedule_tail
+.ret11: mov ar.pfs=loc1
+ mov rp=loc0
+ br.ret.sptk.many rp
+END(ia64_invoke_schedule_tail)
+
+ /*
+ * Setup stack and call do_notify_resume_user(), keeping interrupts
+ * disabled.
+ *
+ * Note that pSys and pNonSys need to be set up by the caller.
+ * We declare 8 input registers so the system call args get preserved,
+ * in case we need to restart a system call.
+ */
+GLOBAL_ENTRY(notify_resume_user)
+ .prologue ASM_UNW_PRLG_RP|ASM_UNW_PRLG_PFS, ASM_UNW_PRLG_GRSAVE(8)
+ alloc loc1=ar.pfs,8,2,3,0 // preserve all eight input regs in case of syscall restart!
+ mov r9=ar.unat
+ mov loc0=rp // save return address
+ mov out0=0 // there is no "oldset"
+ adds out1=8,sp // out1=&sigscratch->ar_pfs
+(pSys) mov out2=1 // out2==1 => we're in a syscall
+ ;;
+(pNonSys) mov out2=0 // out2==0 => not a syscall
+ .fframe 16
+ .spillsp ar.unat, 16
+ st8 [sp]=r9,-16 // allocate space for ar.unat and save it
+ st8 [out1]=loc1,-8 // save ar.pfs, out1=&sigscratch
+ .body
+ br.call.sptk.many rp=do_notify_resume_user
+.ret15: .restore sp
+ adds sp=16,sp // pop scratch stack space
+ ;;
+ ld8 r9=[sp] // load new unat from sigscratch->scratch_unat
+ mov rp=loc0
+ ;;
+ mov ar.unat=r9
+ mov ar.pfs=loc1
+ br.ret.sptk.many rp
+END(notify_resume_user)
+
+ENTRY(sys_rt_sigreturn)
+ PT_REGS_UNWIND_INFO(0)
+ /*
+ * Allocate 8 input registers since ptrace() may clobber them
+ */
+ alloc r2=ar.pfs,8,0,1,0
+ .prologue
+ PT_REGS_SAVES(16)
+ adds sp=-16,sp
+ .body
+ cmp.eq pNonSys,pSys=r0,r0 // sigreturn isn't a normal syscall...
+ ;;
+ /*
+ * leave_kernel() restores f6-f11 from pt_regs, but since the streamlined
+ * syscall-entry path does not save them we save them here instead. Note: we
+ * don't need to save any other registers that are not saved by the stream-lined
+ * syscall path, because restore_sigcontext() restores them.
+ */
+ adds r16=PT(F6)+32,sp
+ adds r17=PT(F7)+32,sp
+ ;;
+ stf.spill [r16]=f6,32
+ stf.spill [r17]=f7,32
+ ;;
+ stf.spill [r16]=f8,32
+ stf.spill [r17]=f9,32
+ ;;
+ stf.spill [r16]=f10
+ stf.spill [r17]=f11
+ adds out0=16,sp // out0 = &sigscratch
+ br.call.sptk.many rp=ia64_rt_sigreturn
+.ret19: .restore sp,0
+ adds sp=16,sp
+ ;;
+ ld8 r9=[sp] // load new ar.unat
+ mov.sptk b7=r8,ia64_leave_kernel
+ ;;
+ mov ar.unat=r9
+ br.many b7
+END(sys_rt_sigreturn)
+
+GLOBAL_ENTRY(ia64_prepare_handle_unaligned)
+ .prologue
+ /*
+ * r16 = fake ar.pfs, we simply need to make sure privilege is still 0
+ */
+ mov r16=r0
+ DO_SAVE_SWITCH_STACK
+ br.call.sptk.many rp=ia64_handle_unaligned // stack frame setup in ivt
+.ret21: .body
+ DO_LOAD_SWITCH_STACK
+ br.cond.sptk.many rp // goes to ia64_leave_kernel
+END(ia64_prepare_handle_unaligned)
+
+ //
+ // unw_init_running(void (*callback)(info, arg), void *arg)
+ //
+# define EXTRA_FRAME_SIZE ((UNW_FRAME_INFO_SIZE+15)&~15)
+
+GLOBAL_ENTRY(unw_init_running)
+ .prologue ASM_UNW_PRLG_RP|ASM_UNW_PRLG_PFS, ASM_UNW_PRLG_GRSAVE(2)
+ alloc loc1=ar.pfs,2,3,3,0
+ ;;
+ ld8 loc2=[in0],8
+ mov loc0=rp
+ mov r16=loc1
+ DO_SAVE_SWITCH_STACK
+ .body
+
+ .prologue ASM_UNW_PRLG_RP|ASM_UNW_PRLG_PFS, ASM_UNW_PRLG_GRSAVE(2)
+ .fframe IA64_SWITCH_STACK_SIZE+EXTRA_FRAME_SIZE
+ SWITCH_STACK_SAVES(EXTRA_FRAME_SIZE)
+ adds sp=-EXTRA_FRAME_SIZE,sp
+ .body
+ ;;
+ adds out0=16,sp // &info
+ mov out1=r13 // current
+ adds out2=16+EXTRA_FRAME_SIZE,sp // &switch_stack
+ br.call.sptk.many rp=unw_init_frame_info
+1: adds out0=16,sp // &info
+ mov b6=loc2
+ mov loc2=gp // save gp across indirect function call
+ ;;
+ ld8 gp=[in0]
+ mov out1=in1 // arg
+ br.call.sptk.many rp=b6 // invoke the callback function
+1: mov gp=loc2 // restore gp
+
+ // For now, we don't allow changing registers from within
+ // unw_init_running; if we ever want to allow that, we'd
+ // have to do a load_switch_stack here:
+ .restore sp
+ adds sp=IA64_SWITCH_STACK_SIZE+EXTRA_FRAME_SIZE,sp
+
+ mov ar.pfs=loc1
+ mov rp=loc0
+ br.ret.sptk.many rp
+END(unw_init_running)
+EXPORT_SYMBOL(unw_init_running)
+
+#ifdef CONFIG_FUNCTION_TRACER
+#ifdef CONFIG_DYNAMIC_FTRACE
+GLOBAL_ENTRY(_mcount)
+ br ftrace_stub
+END(_mcount)
+EXPORT_SYMBOL(_mcount)
+
+.here:
+ br.ret.sptk.many b0
+
+GLOBAL_ENTRY(ftrace_caller)
+ alloc out0 = ar.pfs, 8, 0, 4, 0
+ mov out3 = r0
+ ;;
+ mov out2 = b0
+ add r3 = 0x20, r3
+ mov out1 = r1;
+ br.call.sptk.many b0 = ftrace_patch_gp
+ //this might be called from module, so we must patch gp
+ftrace_patch_gp:
+ movl gp=__gp
+ mov b0 = r3
+ ;;
+.global ftrace_call;
+ftrace_call:
+{
+ .mlx
+ nop.m 0x0
+ movl r3 = .here;;
+}
+ alloc loc0 = ar.pfs, 4, 4, 2, 0
+ ;;
+ mov loc1 = b0
+ mov out0 = b0
+ mov loc2 = r8
+ mov loc3 = r15
+ ;;
+ adds out0 = -MCOUNT_INSN_SIZE, out0
+ mov out1 = in2
+ mov b6 = r3
+
+ br.call.sptk.many b0 = b6
+ ;;
+ mov ar.pfs = loc0
+ mov b0 = loc1
+ mov r8 = loc2
+ mov r15 = loc3
+ br ftrace_stub
+ ;;
+END(ftrace_caller)
+
+#else
+GLOBAL_ENTRY(_mcount)
+ movl r2 = ftrace_stub
+ movl r3 = ftrace_trace_function;;
+ ld8 r3 = [r3];;
+ ld8 r3 = [r3];;
+ cmp.eq p7,p0 = r2, r3
+(p7) br.sptk.many ftrace_stub
+ ;;
+
+ alloc loc0 = ar.pfs, 4, 4, 2, 0
+ ;;
+ mov loc1 = b0
+ mov out0 = b0
+ mov loc2 = r8
+ mov loc3 = r15
+ ;;
+ adds out0 = -MCOUNT_INSN_SIZE, out0
+ mov out1 = in2
+ mov b6 = r3
+
+ br.call.sptk.many b0 = b6
+ ;;
+ mov ar.pfs = loc0
+ mov b0 = loc1
+ mov r8 = loc2
+ mov r15 = loc3
+ br ftrace_stub
+ ;;
+END(_mcount)
+#endif
+
+GLOBAL_ENTRY(ftrace_stub)
+ mov r3 = b0
+ movl r2 = _mcount_ret_helper
+ ;;
+ mov b6 = r2
+ mov b7 = r3
+ br.ret.sptk.many b6
+
+_mcount_ret_helper:
+ mov b0 = r42
+ mov r1 = r41
+ mov ar.pfs = r40
+ br b7
+END(ftrace_stub)
+
+#endif /* CONFIG_FUNCTION_TRACER */
+
+#define __SYSCALL(nr, entry, nargs) data8 entry
+ .rodata
+ .align 8
+ .globl sys_call_table
+sys_call_table:
+#include <asm/syscall_table.h>
+#undef __SYSCALL
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-23 07:19:08 +0000