System call entry and particularly exit code is beyond the limit of what
is reasonable to implement in asm.
This conversion moves all conditional branches out of the asm code,
except for the case that all GPRs should be restored at exit.
Null syscall test is about 5% faster after this patch, because the exit
work is handled under local_irq_disable, and the hard mask and pending
interrupt replay is handled after that, which avoids games with MSR.
Signed-off-by: Nicholas Piggin <npig...@gmail.com>
---
Since v1:
- Fix big endian build (mpe)
- Fix order of exit tracing to after the result registers have been set.
- Move ->softe store before MSR[EE] is set, fix the now obsolete comment.
- More #ifdef tidyups and writing the accounting helpers nicer (Christophe)
- Minor things like move the TM debug store into C
arch/powerpc/include/asm/asm-prototypes.h | 11 -
.../powerpc/include/asm/book3s/64/kup-radix.h | 10 +-
arch/powerpc/include/asm/cputime.h | 24 ++
arch/powerpc/include/asm/ptrace.h | 3 +
arch/powerpc/include/asm/signal.h | 3 +
arch/powerpc/include/asm/switch_to.h | 5 +
arch/powerpc/include/asm/time.h | 3 +
arch/powerpc/kernel/Makefile | 3 +-
arch/powerpc/kernel/entry_64.S | 337 +++---------------
arch/powerpc/kernel/signal.h | 2 -
arch/powerpc/kernel/syscall_64.c | 183 ++++++++++
11 files changed, 277 insertions(+), 307 deletions(-)
create mode 100644 arch/powerpc/kernel/syscall_64.c
diff --git a/arch/powerpc/include/asm/asm-prototypes.h
b/arch/powerpc/include/asm/asm-prototypes.h
index ec1c97a8e8cb..f00ef8924a99 100644
--- a/arch/powerpc/include/asm/asm-prototypes.h
+++ b/arch/powerpc/include/asm/asm-prototypes.h
@@ -92,14 +92,6 @@ long sys_switch_endian(void);
notrace unsigned int __check_irq_replay(void);
void notrace restore_interrupts(void);
-/* ptrace */
-long do_syscall_trace_enter(struct pt_regs *regs);
-void do_syscall_trace_leave(struct pt_regs *regs);
-
-/* process */
-void restore_math(struct pt_regs *regs);
-void restore_tm_state(struct pt_regs *regs);
-
/* prom_init (OpenFirmware) */
unsigned long __init prom_init(unsigned long r3, unsigned long r4,
unsigned long pp,
@@ -110,9 +102,6 @@ unsigned long __init prom_init(unsigned long r3, unsigned
long r4,
void __init early_setup(unsigned long dt_ptr);
void early_setup_secondary(void);
-/* time */
-void accumulate_stolen_time(void);
-
/* misc runtime */
extern u64 __bswapdi2(u64);
extern s64 __lshrdi3(s64, int);
diff --git a/arch/powerpc/include/asm/book3s/64/kup-radix.h
b/arch/powerpc/include/asm/book3s/64/kup-radix.h
index f254de956d6a..83f6bda0542b 100644
--- a/arch/powerpc/include/asm/book3s/64/kup-radix.h
+++ b/arch/powerpc/include/asm/book3s/64/kup-radix.h
@@ -3,6 +3,7 @@
#define _ASM_POWERPC_BOOK3S_64_KUP_RADIX_H
#include <linux/const.h>
+#include <asm/reg.h>
#define AMR_KUAP_BLOCK_READ UL(0x4000000000000000)
#define AMR_KUAP_BLOCK_WRITE UL(0x8000000000000000)
@@ -56,7 +57,14 @@
#ifdef CONFIG_PPC_KUAP
-#include <asm/reg.h>
+#include <asm/mmu.h>
+#include <asm/ptrace.h>
+
+static inline void kuap_check_amr(void)
+{
+ if (IS_ENABLED(CONFIG_PPC_KUAP_DEBUG) &&
mmu_has_feature(MMU_FTR_RADIX_KUAP))
+ WARN_ON_ONCE(mfspr(SPRN_AMR) != AMR_KUAP_BLOCKED);
+}
/*
* We support individually allowing read or write, but we don't support nesting
diff --git a/arch/powerpc/include/asm/cputime.h
b/arch/powerpc/include/asm/cputime.h
index 2431b4ada2fa..c43614cffaac 100644
--- a/arch/powerpc/include/asm/cputime.h
+++ b/arch/powerpc/include/asm/cputime.h
@@ -60,6 +60,30 @@ static inline void arch_vtime_task_switch(struct task_struct
*prev)
}
#endif
+static inline void account_cpu_user_entry(void)
+{
+ unsigned long tb = mftb();
+ struct cpu_accounting_data *acct = get_accounting(current);
+
+ acct->utime += (tb - acct->starttime_user);
+ acct->starttime = tb;
+}
+static inline void account_cpu_user_exit(void)
+{
+ unsigned long tb = mftb();
+ struct cpu_accounting_data *acct = get_accounting(current);
+
+ acct->stime += (tb - acct->starttime);
+ acct->starttime_user = tb;
+}
+
#endif /* __KERNEL__ */
+#else /* CONFIG_VIRT_CPU_ACCOUNTING_NATIVE */
+static inline void account_cpu_user_entry(void)
+{
+}
+static inline void account_cpu_user_exit(void)
+{
+}
#endif /* CONFIG_VIRT_CPU_ACCOUNTING_NATIVE */
#endif /* __POWERPC_CPUTIME_H */
diff --git a/arch/powerpc/include/asm/ptrace.h
b/arch/powerpc/include/asm/ptrace.h
index feee1b21bbd5..af363086403a 100644
--- a/arch/powerpc/include/asm/ptrace.h
+++ b/arch/powerpc/include/asm/ptrace.h
@@ -138,6 +138,9 @@ extern unsigned long profile_pc(struct pt_regs *regs);
#define profile_pc(regs) instruction_pointer(regs)
#endif
+long do_syscall_trace_enter(struct pt_regs *regs);
+void do_syscall_trace_leave(struct pt_regs *regs);
+
#define kernel_stack_pointer(regs) ((regs)->gpr[1])
static inline int is_syscall_success(struct pt_regs *regs)
{
diff --git a/arch/powerpc/include/asm/signal.h
b/arch/powerpc/include/asm/signal.h
index 0803ca8b9149..99e1c6de27bc 100644
--- a/arch/powerpc/include/asm/signal.h
+++ b/arch/powerpc/include/asm/signal.h
@@ -6,4 +6,7 @@
#include <uapi/asm/signal.h>
#include <uapi/asm/ptrace.h>
+struct pt_regs;
+void do_notify_resume(struct pt_regs *regs, unsigned long thread_info_flags);
+
#endif /* _ASM_POWERPC_SIGNAL_H */
diff --git a/arch/powerpc/include/asm/switch_to.h
b/arch/powerpc/include/asm/switch_to.h
index 5b03d8a82409..476008bc3d08 100644
--- a/arch/powerpc/include/asm/switch_to.h
+++ b/arch/powerpc/include/asm/switch_to.h
@@ -5,6 +5,7 @@
#ifndef _ASM_POWERPC_SWITCH_TO_H
#define _ASM_POWERPC_SWITCH_TO_H
+#include <linux/sched.h>
#include <asm/reg.h>
struct thread_struct;
@@ -22,6 +23,10 @@ extern void switch_booke_debug_regs(struct debug_reg
*new_debug);
extern int emulate_altivec(struct pt_regs *);
+void restore_math(struct pt_regs *regs);
+
+void restore_tm_state(struct pt_regs *regs);
+
extern void flush_all_to_thread(struct task_struct *);
extern void giveup_all(struct task_struct *);
diff --git a/arch/powerpc/include/asm/time.h b/arch/powerpc/include/asm/time.h
index 54f4ec1f9fab..ba97858c9d76 100644
--- a/arch/powerpc/include/asm/time.h
+++ b/arch/powerpc/include/asm/time.h
@@ -199,5 +199,8 @@ DECLARE_PER_CPU(u64, decrementers_next_tb);
/* Convert timebase ticks to nanoseconds */
unsigned long long tb_to_ns(unsigned long long tb_ticks);
+/* SPLPAR */
+void accumulate_stolen_time(void);
+
#endif /* __KERNEL__ */
#endif /* __POWERPC_TIME_H */
diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile
index 56dfa7a2a6f2..7f53cc07f933 100644
--- a/arch/powerpc/kernel/Makefile
+++ b/arch/powerpc/kernel/Makefile
@@ -52,7 +52,8 @@ obj-y := cputable.o ptrace.o
syscalls.o \
of_platform.o prom_parse.o
obj-$(CONFIG_PPC64) += setup_64.o sys_ppc32.o \
signal_64.o ptrace32.o \
- paca.o nvram_64.o firmware.o
+ paca.o nvram_64.o firmware.o \
+ syscall_64.o
obj-$(CONFIG_VDSO32) += vdso32/
obj-$(CONFIG_PPC_WATCHDOG) += watchdog.o
obj-$(CONFIG_HAVE_HW_BREAKPOINT) += hw_breakpoint.o
diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S
index 5a3e0b5c9ad1..15bc2a872a76 100644
--- a/arch/powerpc/kernel/entry_64.S
+++ b/arch/powerpc/kernel/entry_64.S
@@ -63,12 +63,6 @@ exception_marker:
.globl system_call_common
system_call_common:
-#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
-BEGIN_FTR_SECTION
- extrdi. r10, r12, 1, (63-MSR_TS_T_LG) /* transaction active? */
- bne .Ltabort_syscall
-END_FTR_SECTION_IFSET(CPU_FTR_TM)
-#endif
mr r10,r1
ld r1,PACAKSAVE(r13)
std r10,0(r1)
@@ -76,350 +70,111 @@ END_FTR_SECTION_IFSET(CPU_FTR_TM)
std r12,_MSR(r1)
std r0,GPR0(r1)
std r10,GPR1(r1)
+ std r2,GPR2(r1)
#ifdef CONFIG_PPC_FSL_BOOK3E
START_BTB_FLUSH_SECTION
BTB_FLUSH(r10)
END_BTB_FLUSH_SECTION
#endif
- ACCOUNT_CPU_USER_ENTRY(r13, r10, r11)
- std r2,GPR2(r1)
+ ld r2,PACATOC(r13)
+ mfcr r12
+ li r11,0
+ /* Can we avoid saving r3-r8 in common case? */
std r3,GPR3(r1)
- mfcr r2
std r4,GPR4(r1)
std r5,GPR5(r1)
std r6,GPR6(r1)
std r7,GPR7(r1)
std r8,GPR8(r1)
- li r11,0
+ /* Zero r9-r12, this should only be required when restoring all GPRs */
std r11,GPR9(r1)
std r11,GPR10(r1)
std r11,GPR11(r1)
std r11,GPR12(r1)
- std r11,_XER(r1)
- std r11,_CTR(r1)
std r9,GPR13(r1)
SAVE_NVGPRS(r1)
+ std r11,_XER(r1)
+ std r11,_CTR(r1)
mflr r10
+
/*
* This clears CR0.SO (bit 28), which is the error indication on
* return from this system call.
*/
- rldimi r2,r11,28,(63-28)
+ rldimi r12,r11,28,(63-28)
li r11,0xc00
std r10,_LINK(r1)
std r11,_TRAP(r1)
+ std r12,_CCR(r1)
std r3,ORIG_GPR3(r1)
- std r2,_CCR(r1)
- ld r2,PACATOC(r13)
- addi r9,r1,STACK_FRAME_OVERHEAD
+ addi r10,r1,STACK_FRAME_OVERHEAD
ld r11,exception_marker@toc(r2)
- std r11,-16(r9) /* "regshere" marker */
-
- kuap_check_amr r10, r11
-
-#if defined(CONFIG_VIRT_CPU_ACCOUNTING_NATIVE) && defined(CONFIG_PPC_SPLPAR)
-BEGIN_FW_FTR_SECTION
- /* see if there are any DTL entries to process */
- ld r10,PACALPPACAPTR(r13) /* get ptr to VPA */
- ld r11,PACA_DTL_RIDX(r13) /* get log read index */
- addi r10,r10,LPPACA_DTLIDX
- LDX_BE r10,0,r10 /* get log write index */
- cmpd r11,r10
- beq+ 33f
- bl accumulate_stolen_time
- REST_GPR(0,r1)
- REST_4GPRS(3,r1)
- REST_2GPRS(7,r1)
- addi r9,r1,STACK_FRAME_OVERHEAD
-33:
-END_FW_FTR_SECTION_IFSET(FW_FEATURE_SPLPAR)
-#endif /* CONFIG_VIRT_CPU_ACCOUNTING_NATIVE && CONFIG_PPC_SPLPAR */
-
- /*
- * A syscall should always be called with interrupts enabled
- * so we just unconditionally hard-enable here. When some kind
- * of irq tracing is used, we additionally check that condition
- * is correct
- */
-#if defined(CONFIG_PPC_IRQ_SOFT_MASK_DEBUG) && defined(CONFIG_BUG)
- lbz r10,PACAIRQSOFTMASK(r13)
-1: tdnei r10,IRQS_ENABLED
- EMIT_BUG_ENTRY 1b,__FILE__,__LINE__,BUGFLAG_WARNING
-#endif
-
-#ifdef CONFIG_PPC_BOOK3E
- wrteei 1
-#else
- li r11,MSR_RI
- ori r11,r11,MSR_EE
- mtmsrd r11,1
-#endif /* CONFIG_PPC_BOOK3E */
-
-system_call: /* label this so stack traces look sane */
- /* We do need to set SOFTE in the stack frame or the return
- * from interrupt will be painful
- */
- li r10,IRQS_ENABLED
- std r10,SOFTE(r1)
+ std r11,-16(r10) /* "regshere" marker */
- ld r11, PACA_THREAD_INFO(r13)
- ld r10,TI_FLAGS(r11)
- andi. r11,r10,_TIF_SYSCALL_DOTRACE
- bne .Lsyscall_dotrace /* does not return */
- cmpldi 0,r0,NR_syscalls
- bge- .Lsyscall_enosys
+ /* Calling convention has r9 = orig r0, r10 = regs */
+ mr r9,r0
+ bl system_call_exception
-.Lsyscall:
-/*
- * Need to vector to 32 Bit or default sys_call_table here,
- * based on caller's run-mode / personality.
- */
- ld r11,SYS_CALL_TABLE@toc(2)
- andis. r10,r10,_TIF_32BIT@h
- beq 15f
- ld r11,COMPAT_SYS_CALL_TABLE@toc(2)
- clrldi r3,r3,32
- clrldi r4,r4,32
- clrldi r5,r5,32
- clrldi r6,r6,32
- clrldi r7,r7,32
- clrldi r8,r8,32
-15:
- slwi r0,r0,3
-
- barrier_nospec_asm
- /*
- * Prevent the load of the handler below (based on the user-passed
- * system call number) being speculatively executed until the test
- * against NR_syscalls and branch to .Lsyscall_enosys above has
- * committed.
- */
-
- ldx r12,r11,r0 /* Fetch system call handler [ptr] */
- mtctr r12
- bctrl /* Call handler */
-
- /* syscall_exit can exit to kernel mode, via ret_from_kernel_thread */
.Lsyscall_exit:
- std r3,RESULT(r1)
+ addi r4,r1,STACK_FRAME_OVERHEAD
+ bl syscall_exit_prepare
-#ifdef CONFIG_DEBUG_RSEQ
- /* Check whether the syscall is issued inside a restartable sequence */
- addi r3,r1,STACK_FRAME_OVERHEAD
- bl rseq_syscall
- ld r3,RESULT(r1)
-#endif
-
- ld r12, PACA_THREAD_INFO(r13)
-
- ld r8,_MSR(r1)
-
-/*
- * This is a few instructions into the actual syscall exit path (which actually
- * starts at .Lsyscall_exit) to cater to kprobe blacklisting and to reduce the
- * number of visible symbols for profiling purposes.
- *
- * We can probe from system_call until this point as MSR_RI is set. But once it
- * is cleared below, we won't be able to take a trap.
- *
- * This is blacklisted from kprobes further below with _ASM_NOKPROBE_SYMBOL().
- */
-system_call_exit:
- /*
- * Disable interrupts so current_thread_info()->flags can't change,
- * and so that we don't get interrupted after loading SRR0/1.
- *
- * Leave MSR_RI enabled for now, because with THREAD_INFO_IN_TASK we
- * could fault on the load of the TI_FLAGS below.
- */
-#ifdef CONFIG_PPC_BOOK3E
- wrteei 0
-#else
- li r11,MSR_RI
- mtmsrd r11,1
-#endif /* CONFIG_PPC_BOOK3E */
-
- ld r9,TI_FLAGS(r12)
- li r11,-MAX_ERRNO
- andi.
r0,r9,(_TIF_SYSCALL_DOTRACE|_TIF_SINGLESTEP|_TIF_USER_WORK_MASK|_TIF_PERSYSCALL_MASK)
- bne- .Lsyscall_exit_work
+ ld r2,_CCR(r1)
+ ld r4,_NIP(r1)
+ ld r5,_MSR(r1)
+ ld r6,_LINK(r1)
- andi. r0,r8,MSR_FP
- beq 2f
-#ifdef CONFIG_ALTIVEC
- andis. r0,r8,MSR_VEC@h
- bne 3f
-#endif
-2: addi r3,r1,STACK_FRAME_OVERHEAD
- bl restore_math
- ld r8,_MSR(r1)
- ld r3,RESULT(r1)
- li r11,-MAX_ERRNO
-
-3: cmpld r3,r11
- ld r5,_CCR(r1)
- bge- .Lsyscall_error
-.Lsyscall_error_cont:
- ld r7,_NIP(r1)
BEGIN_FTR_SECTION
stdcx. r0,0,r1 /* to clear the reservation */
END_FTR_SECTION_IFCLR(CPU_FTR_STCX_CHECKS_ADDRESS)
- andi. r6,r8,MSR_PR
- ld r4,_LINK(r1)
- kuap_check_amr r10, r11
+ mtspr SPRN_SRR0,r4
+ mtspr SPRN_SRR1,r5
+ mtlr r6
-#ifdef CONFIG_PPC_BOOK3S
- /*
- * Clear MSR_RI, MSR_EE is already and remains disabled. We could do
- * this later, but testing shows that doing it here causes less slow
- * down than doing it closer to the rfid.
- */
- li r11,0
- mtmsrd r11,1
-#endif
-
- beq- 1f
- ACCOUNT_CPU_USER_EXIT(r13, r11, r12)
+ cmpdi r3,0
+ bne syscall_restore_regs
+.Lsyscall_restore_regs_cont:
BEGIN_FTR_SECTION
HMT_MEDIUM_LOW
END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
-#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
- std r8, PACATMSCRATCH(r13)
-#endif
-
/*
* We don't need to restore AMR on the way back to userspace for KUAP.
* The value of AMR only matters while we're in the kernel.
*/
- ld r13,GPR13(r1) /* only restore r13 if returning to usermode */
+ mtcr r2
ld r2,GPR2(r1)
+ ld r3,GPR3(r1)
+ ld r13,GPR13(r1)
ld r1,GPR1(r1)
- mtlr r4
- mtcr r5
- mtspr SPRN_SRR0,r7
- mtspr SPRN_SRR1,r8
RFI_TO_USER
b . /* prevent speculative execution */
+_ASM_NOKPROBE_SYMBOL(system_call_common);
-1: /* exit to kernel */
- kuap_restore_amr r2
-
- ld r2,GPR2(r1)
- ld r1,GPR1(r1)
- mtlr r4
- mtcr r5
- mtspr SPRN_SRR0,r7
- mtspr SPRN_SRR1,r8
- RFI_TO_KERNEL
- b . /* prevent speculative execution */
-
-.Lsyscall_error:
- oris r5,r5,0x1000 /* Set SO bit in CR */
- neg r3,r3
- std r5,_CCR(r1)
- b .Lsyscall_error_cont
-
-/* Traced system call support */
-.Lsyscall_dotrace:
- addi r3,r1,STACK_FRAME_OVERHEAD
- bl do_syscall_trace_enter
-
- /*
- * We use the return value of do_syscall_trace_enter() as the syscall
- * number. If the syscall was rejected for any reason
do_syscall_trace_enter()
- * returns an invalid syscall number and the test below against
- * NR_syscalls will fail.
- */
- mr r0,r3
-
- /* Restore argument registers just clobbered and/or possibly changed. */
- ld r3,GPR3(r1)
- ld r4,GPR4(r1)
- ld r5,GPR5(r1)
- ld r6,GPR6(r1)
- ld r7,GPR7(r1)
- ld r8,GPR8(r1)
-
- /* Repopulate r9 and r10 for the syscall path */
- addi r9,r1,STACK_FRAME_OVERHEAD
- ld r10, PACA_THREAD_INFO(r13)
- ld r10,TI_FLAGS(r10)
-
- cmpldi r0,NR_syscalls
- blt+ .Lsyscall
-
- /* Return code is already in r3 thanks to do_syscall_trace_enter() */
- b .Lsyscall_exit
-
-
-.Lsyscall_enosys:
- li r3,-ENOSYS
- b .Lsyscall_exit
-
-.Lsyscall_exit_work:
- /* If TIF_RESTOREALL is set, don't scribble on either r3 or ccr.
- If TIF_NOERROR is set, just save r3 as it is. */
-
- andi. r0,r9,_TIF_RESTOREALL
- beq+ 0f
+syscall_restore_regs:
+ ld r3,_CTR(r1)
+ ld r4,_XER(r1)
REST_NVGPRS(r1)
- b 2f
-0: cmpld r3,r11 /* r11 is -MAX_ERRNO */
- blt+ 1f
- andi. r0,r9,_TIF_NOERROR
- bne- 1f
- ld r5,_CCR(r1)
- neg r3,r3
- oris r5,r5,0x1000 /* Set SO bit in CR */
- std r5,_CCR(r1)
-1: std r3,GPR3(r1)
-2: andi. r0,r9,(_TIF_PERSYSCALL_MASK)
- beq 4f
-
- /* Clear per-syscall TIF flags if any are set. */
-
- li r11,_TIF_PERSYSCALL_MASK
- addi r12,r12,TI_FLAGS
-3: ldarx r10,0,r12
- andc r10,r10,r11
- stdcx. r10,0,r12
- bne- 3b
- subi r12,r12,TI_FLAGS
-
-4: /* Anything else left to do? */
-BEGIN_FTR_SECTION
- lis r3,DEFAULT_PPR@highest /* Set default PPR */
- sldi r3,r3,32 /* bits 11-13 are used for ppr */
- std r3,_PPR(r1)
-END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
-
- andi. r0,r9,(_TIF_SYSCALL_DOTRACE|_TIF_SINGLESTEP)
- beq ret_from_except_lite
-
- /* Re-enable interrupts */
-#ifdef CONFIG_PPC_BOOK3E
- wrteei 1
-#else
- li r10,MSR_RI
- ori r10,r10,MSR_EE
- mtmsrd r10,1
-#endif /* CONFIG_PPC_BOOK3E */
-
- addi r3,r1,STACK_FRAME_OVERHEAD
- bl do_syscall_trace_leave
- b ret_from_except
+ mtctr r3
+ mtspr SPRN_XER,r4
+ ld r0,GPR0(r1)
+ REST_8GPRS(4, r1)
+ ld r12,GPR12(r1)
+ b .Lsyscall_restore_regs_cont
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
-.Ltabort_syscall:
+_GLOBAL(tabort_syscall)
/* Firstly we need to enable TM in the kernel */
mfmsr r10
li r9, 1
rldimi r10, r9, MSR_TM_LG, 63-MSR_TM_LG
mtmsrd r10, 0
+ ld r11,_NIP(r13)
+ ld r12,_MSR(r13)
+
/* tabort, this dooms the transaction, nothing else */
li r9, (TM_CAUSE_SYSCALL|TM_CAUSE_PERSISTENT)
TABORT(R9)
@@ -438,8 +193,6 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
RFI_TO_USER
b . /* prevent speculative execution */
#endif
-_ASM_NOKPROBE_SYMBOL(system_call_common);
-_ASM_NOKPROBE_SYMBOL(system_call_exit);
_GLOBAL(ret_from_fork)
bl schedule_tail
diff --git a/arch/powerpc/kernel/signal.h b/arch/powerpc/kernel/signal.h
index 800433685888..d396efca4068 100644
--- a/arch/powerpc/kernel/signal.h
+++ b/arch/powerpc/kernel/signal.h
@@ -10,8 +10,6 @@
#ifndef _POWERPC_ARCH_SIGNAL_H
#define _POWERPC_ARCH_SIGNAL_H
-extern void do_notify_resume(struct pt_regs *regs, unsigned long
thread_info_flags);
-
extern void __user *get_sigframe(struct ksignal *ksig, unsigned long sp,
size_t frame_size, int is_32);
diff --git a/arch/powerpc/kernel/syscall_64.c b/arch/powerpc/kernel/syscall_64.c
new file mode 100644
index 000000000000..2ae4b7a9eff5
--- /dev/null
+++ b/arch/powerpc/kernel/syscall_64.c
@@ -0,0 +1,183 @@
+#include <linux/err.h>
+#include <asm/book3s/64/kup-radix.h>
+#include <asm/cputime.h>
+#include <asm/hw_irq.h>
+#include <asm/paca.h>
+#include <asm/ptrace.h>
+#include <asm/reg.h>
+#include <asm/signal.h>
+#include <asm/switch_to.h>
+#include <asm/syscall.h>
+#include <asm/time.h>
+
+extern void __noreturn tabort_syscall(void);
+
+typedef long (*syscall_fn)(long, long, long, long, long, long);
+
+long system_call_exception(long r3, long r4, long r5, long r6, long r7, long
r8, unsigned long r0, struct pt_regs *regs)
+{
+ unsigned long ti_flags;
+ syscall_fn f;
+
+ BUG_ON(!(regs->msr & MSR_PR));
+
+ if (IS_ENABLED(CONFIG_PPC_TRANSACTIONAL_MEM) &&
+ unlikely(regs->msr & MSR_TS_T))
+ tabort_syscall();
+
+ account_cpu_user_entry();
+
+#ifdef CONFIG_PPC_SPLPAR
+ if (IS_ENABLED(CONFIG_VIRT_CPU_ACCOUNTING_NATIVE) &&
+ firmware_has_feature(FW_FEATURE_SPLPAR)) {
+ struct lppaca *lp = get_lppaca();
+
+ if (unlikely(local_paca->dtl_ridx != lp->dtl_idx))
+ accumulate_stolen_time();
+ }
+#endif
+
+ kuap_check_amr();
+
+ /*
+ * A syscall should always be called with interrupts enabled
+ * so we just unconditionally hard-enable here. When some kind
+ * of irq tracing is used, we additionally check that condition
+ * is correct
+ */
+ if (IS_ENABLED(CONFIG_PPC_IRQ_SOFT_MASK_DEBUG)) {
+ WARN_ON(irq_soft_mask_return() != IRQS_ENABLED);
+ WARN_ON(local_paca->irq_happened);
+ }
+ /*
+ * This is not required for the syscall exit path, but makes the
+ * stack frame look nicer. If this was initialised in the first stack
+ * frame, or if the unwinder was taught the first stack frame always
+ * returns to user with IRQS_ENABLED, this store could be avoided!
+ */
+ regs->softe = IRQS_ENABLED;
+
+ __hard_irq_enable();
+
+ ti_flags = current_thread_info()->flags;
+ if (unlikely(ti_flags & _TIF_SYSCALL_DOTRACE)) {
+ /*
+ * We use the return value of do_syscall_trace_enter() as the
+ * syscall number. If the syscall was rejected for any reason
+ * do_syscall_trace_enter() returns an invalid syscall number
+ * and the test below against NR_syscalls will fail.
+ */
+ r0 = do_syscall_trace_enter(regs);
+ }
+
+ if (unlikely(r0 >= NR_syscalls))
+ return -ENOSYS;
+
+ /* May be faster to do array_index_nospec? */
+ barrier_nospec();
+
+ if (unlikely(ti_flags & _TIF_32BIT)) {
+ f = (void *)compat_sys_call_table[r0];
+
+ r3 &= 0x00000000ffffffffULL;
+ r4 &= 0x00000000ffffffffULL;
+ r5 &= 0x00000000ffffffffULL;
+ r6 &= 0x00000000ffffffffULL;
+ r7 &= 0x00000000ffffffffULL;
+ r8 &= 0x00000000ffffffffULL;
+
+ } else {
+ f = (void *)sys_call_table[r0];
+ }
+
+ return f(r3, r4, r5, r6, r7, r8);
+}
+
+unsigned long syscall_exit_prepare(unsigned long r3, struct pt_regs *regs)
+{
+ unsigned long *ti_flagsp = ¤t_thread_info()->flags;
+ unsigned long ti_flags;
+ unsigned long ret = 0;
+
+ regs->result = r3;
+
+ /* Check whether the syscall is issued inside a restartable sequence */
+ rseq_syscall(regs);
+
+ ti_flags = *ti_flagsp;
+
+ if (unlikely(r3 >= (unsigned long)-MAX_ERRNO)) {
+ if (likely(!(ti_flags & (_TIF_NOERROR | _TIF_RESTOREALL)))) {
+ r3 = -r3;
+ regs->ccr |= 0x10000000; /* Set SO bit in CR */
+ }
+ }
+
+ if (unlikely(ti_flags & _TIF_PERSYSCALL_MASK)) {
+ if (ti_flags & _TIF_RESTOREALL)
+ ret = _TIF_RESTOREALL;
+ else
+ regs->gpr[3] = r3;
+ clear_bits(_TIF_PERSYSCALL_MASK, ti_flagsp);
+ } else {
+ regs->gpr[3] = r3;
+ }
+
+ if (unlikely(ti_flags & _TIF_SYSCALL_DOTRACE))
+ do_syscall_trace_leave(regs);
+
+again:
+ local_irq_disable();
+ ti_flags = READ_ONCE(*ti_flagsp);
+ while (unlikely(ti_flags & _TIF_USER_WORK_MASK)) {
+ local_irq_enable();
+ if (ti_flags & _TIF_NEED_RESCHED) {
+ schedule();
+ } else {
+ /*
+ * SIGPENDING must restore signal handler function
+ * argument GPRs, and some non-volatiles (e.g., r1).
+ * Restore all for now. This could be made lighter.
+ */
+ if (ti_flags & _TIF_SIGPENDING)
+ ret |= _TIF_RESTOREALL;
+ do_notify_resume(regs, ti_flags);
+ }
+ local_irq_disable();
+ ti_flags = READ_ONCE(*ti_flagsp);
+ }
+
+ if (IS_ENABLED(CONFIG_PPC_FPU)) {
+ unsigned long mathflags = MSR_FP;
+
+ if (IS_ENABLED(CONFIG_ALTIVEC))
+ mathflags |= MSR_VEC;
+
+ if ((regs->msr & mathflags) != mathflags)
+ restore_math(regs);
+ }
+
+ /* This pattern matches prep_irq_for_idle */
+ __mtmsrd(0, 1); /* Disable MSR_EE and MSR_RI */
+ if (unlikely(lazy_irq_pending())) {
+ __mtmsrd(MSR_RI, 1);
+ local_paca->irq_happened |= PACA_IRQ_HARD_DIS;
+ local_irq_enable();
+ /* Took an interrupt which may have more exit work to do. */
+ goto again;
+ }
+ trace_hardirqs_on();
+ local_paca->irq_happened &= ~PACA_IRQ_HARD_DIS;
+ irq_soft_mask_set(IRQS_ENABLED);
+
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+ local_paca->tm_scratch = regs->msr;
+#endif
+
+ kuap_check_amr();
+
+ account_cpu_user_exit();
+
+ return ret;
+}
+
--
2.22.0
