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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) data8 entry
.rodata
.align 8
.globl sys_call_table
sys_call_table:
#include <asm/syscall_table.h>