diff options
Diffstat (limited to 'arch/powerpc/kernel/syscall_64.c')
| -rw-r--r-- | arch/powerpc/kernel/syscall_64.c | 383 |
1 files changed, 0 insertions, 383 deletions
diff --git a/arch/powerpc/kernel/syscall_64.c b/arch/powerpc/kernel/syscall_64.c deleted file mode 100644 index 79edba3ab312..000000000000 --- a/arch/powerpc/kernel/syscall_64.c +++ /dev/null @@ -1,383 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-or-later - -#include <linux/err.h> -#include <asm/asm-prototypes.h> -#include <asm/book3s/64/kup-radix.h> -#include <asm/cputime.h> -#include <asm/hw_irq.h> -#include <asm/kprobes.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> -#include <asm/unistd.h> - -typedef long (*syscall_fn)(long, long, long, long, long, long); - -/* Has to run notrace because it is entered not completely "reconciled" */ -notrace long system_call_exception(long r3, long r4, long r5, - long r6, long r7, long r8, - unsigned long r0, struct pt_regs *regs) -{ - syscall_fn f; - - if (IS_ENABLED(CONFIG_PPC_IRQ_SOFT_MASK_DEBUG)) - BUG_ON(irq_soft_mask_return() != IRQS_ALL_DISABLED); - - trace_hardirqs_off(); /* finish reconciling */ - - if (IS_ENABLED(CONFIG_PPC_BOOK3S)) - BUG_ON(!(regs->msr & MSR_RI)); - BUG_ON(!(regs->msr & MSR_PR)); - BUG_ON(!FULL_REGS(regs)); - BUG_ON(regs->softe != IRQS_ENABLED); - - kuap_check_amr(); - - 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 = local_paca->lppaca_ptr; - - if (unlikely(local_paca->dtl_ridx != be64_to_cpu(lp->dtl_idx))) - accumulate_stolen_time(); - } -#endif - - /* - * 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; - - local_irq_enable(); - - if (unlikely(current_thread_info()->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 against NR_syscalls will fail and the return - * value to be used is in regs->gpr[3]. - */ - r0 = do_syscall_trace_enter(regs); - if (unlikely(r0 >= NR_syscalls)) - return regs->gpr[3]; - r3 = regs->gpr[3]; - r4 = regs->gpr[4]; - r5 = regs->gpr[5]; - r6 = regs->gpr[6]; - r7 = regs->gpr[7]; - r8 = regs->gpr[8]; - - } else if (unlikely(r0 >= NR_syscalls)) { - return -ENOSYS; - } - - /* May be faster to do array_index_nospec? */ - barrier_nospec(); - - if (unlikely(is_32bit_task())) { - 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); -} - -/* - * local irqs must be disabled. Returns false if the caller must re-enable - * them, check for new work, and try again. - */ -static notrace inline bool prep_irq_for_enabled_exit(void) -{ - /* This must be done with RI=1 because tracing may touch vmaps */ - trace_hardirqs_on(); - - /* This pattern matches prep_irq_for_idle */ - __hard_EE_RI_disable(); - if (unlikely(lazy_irq_pending_nocheck())) { - /* Took an interrupt, may have more exit work to do. */ - __hard_RI_enable(); - trace_hardirqs_off(); - local_paca->irq_happened |= PACA_IRQ_HARD_DIS; - - return false; - } - local_paca->irq_happened = 0; - irq_soft_mask_set(IRQS_ENABLED); - - return true; -} - -/* - * This should be called after a syscall returns, with r3 the return value - * from the syscall. If this function returns non-zero, the system call - * exit assembly should additionally load all GPR registers and CTR and XER - * from the interrupt frame. - * - * The function graph tracer can not trace the return side of this function, - * because RI=0 and soft mask state is "unreconciled", so it is marked notrace. - */ -notrace 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; - - kuap_check_amr(); - - 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); - ret |= _TIF_RESTOREALL; - } - -again: - local_irq_disable(); - ti_flags = READ_ONCE(*ti_flagsp); - while (unlikely(ti_flags & (_TIF_USER_WORK_MASK & ~_TIF_RESTORE_TM))) { - 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_BOOK3S) && IS_ENABLED(CONFIG_PPC_FPU)) { - if (IS_ENABLED(CONFIG_PPC_TRANSACTIONAL_MEM) && - unlikely((ti_flags & _TIF_RESTORE_TM))) { - restore_tm_state(regs); - } else { - unsigned long mathflags = MSR_FP; - - if (cpu_has_feature(CPU_FTR_VSX)) - mathflags |= MSR_VEC | MSR_VSX; - else if (cpu_has_feature(CPU_FTR_ALTIVEC)) - mathflags |= MSR_VEC; - - if ((regs->msr & mathflags) != mathflags) - restore_math(regs); - } - } - - if (unlikely(!prep_irq_for_enabled_exit())) { - local_irq_enable(); - goto again; - } - -#ifdef CONFIG_PPC_TRANSACTIONAL_MEM - local_paca->tm_scratch = regs->msr; -#endif - - account_cpu_user_exit(); - - return ret; -} - -#ifdef CONFIG_PPC_BOOK3S /* BOOK3E not yet using this */ -notrace unsigned long interrupt_exit_user_prepare(struct pt_regs *regs, unsigned long msr) -{ -#ifdef CONFIG_PPC_BOOK3E - struct thread_struct *ts = ¤t->thread; -#endif - unsigned long *ti_flagsp = ¤t_thread_info()->flags; - unsigned long ti_flags; - unsigned long flags; - unsigned long ret = 0; - - if (IS_ENABLED(CONFIG_PPC_BOOK3S)) - BUG_ON(!(regs->msr & MSR_RI)); - BUG_ON(!(regs->msr & MSR_PR)); - BUG_ON(!FULL_REGS(regs)); - BUG_ON(regs->softe != IRQS_ENABLED); - - /* - * We don't need to restore AMR on the way back to userspace for KUAP. - * AMR can only have been unlocked if we interrupted the kernel. - */ - kuap_check_amr(); - - local_irq_save(flags); - -again: - ti_flags = READ_ONCE(*ti_flagsp); - while (unlikely(ti_flags & (_TIF_USER_WORK_MASK & ~_TIF_RESTORE_TM))) { - local_irq_enable(); /* returning to user: may enable */ - if (ti_flags & _TIF_NEED_RESCHED) { - schedule(); - } else { - 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_BOOK3S) && IS_ENABLED(CONFIG_PPC_FPU)) { - if (IS_ENABLED(CONFIG_PPC_TRANSACTIONAL_MEM) && - unlikely((ti_flags & _TIF_RESTORE_TM))) { - restore_tm_state(regs); - } else { - unsigned long mathflags = MSR_FP; - - if (cpu_has_feature(CPU_FTR_VSX)) - mathflags |= MSR_VEC | MSR_VSX; - else if (cpu_has_feature(CPU_FTR_ALTIVEC)) - mathflags |= MSR_VEC; - - if ((regs->msr & mathflags) != mathflags) - restore_math(regs); - } - } - - if (unlikely(!prep_irq_for_enabled_exit())) { - local_irq_enable(); - local_irq_disable(); - goto again; - } - -#ifdef CONFIG_PPC_BOOK3E - if (unlikely(ts->debug.dbcr0 & DBCR0_IDM)) { - /* - * Check to see if the dbcr0 register is set up to debug. - * Use the internal debug mode bit to do this. - */ - mtmsr(mfmsr() & ~MSR_DE); - mtspr(SPRN_DBCR0, ts->debug.dbcr0); - mtspr(SPRN_DBSR, -1); - } -#endif - -#ifdef CONFIG_PPC_TRANSACTIONAL_MEM - local_paca->tm_scratch = regs->msr; -#endif - - account_cpu_user_exit(); - - return ret; -} - -void unrecoverable_exception(struct pt_regs *regs); -void preempt_schedule_irq(void); - -notrace unsigned long interrupt_exit_kernel_prepare(struct pt_regs *regs, unsigned long msr) -{ - unsigned long *ti_flagsp = ¤t_thread_info()->flags; - unsigned long flags; - unsigned long ret = 0; - unsigned long amr; - - if (IS_ENABLED(CONFIG_PPC_BOOK3S) && unlikely(!(regs->msr & MSR_RI))) - unrecoverable_exception(regs); - BUG_ON(regs->msr & MSR_PR); - BUG_ON(!FULL_REGS(regs)); - - amr = kuap_get_and_check_amr(); - - if (unlikely(*ti_flagsp & _TIF_EMULATE_STACK_STORE)) { - clear_bits(_TIF_EMULATE_STACK_STORE, ti_flagsp); - ret = 1; - } - - local_irq_save(flags); - - if (regs->softe == IRQS_ENABLED) { - /* Returning to a kernel context with local irqs enabled. */ - WARN_ON_ONCE(!(regs->msr & MSR_EE)); -again: - if (IS_ENABLED(CONFIG_PREEMPT)) { - /* Return to preemptible kernel context */ - if (unlikely(*ti_flagsp & _TIF_NEED_RESCHED)) { - if (preempt_count() == 0) - preempt_schedule_irq(); - } - } - - if (unlikely(!prep_irq_for_enabled_exit())) { - /* - * Can't local_irq_restore to replay if we were in - * interrupt context. Must replay directly. - */ - if (irqs_disabled_flags(flags)) { - replay_soft_interrupts(); - } else { - local_irq_restore(flags); - local_irq_save(flags); - } - /* Took an interrupt, may have more exit work to do. */ - goto again; - } - } else { - /* Returning to a kernel context with local irqs disabled. */ - __hard_EE_RI_disable(); - if (regs->msr & MSR_EE) - local_paca->irq_happened &= ~PACA_IRQ_HARD_DIS; - } - - -#ifdef CONFIG_PPC_TRANSACTIONAL_MEM - local_paca->tm_scratch = regs->msr; -#endif - - /* - * Don't want to mfspr(SPRN_AMR) here, because this comes after mtmsr, - * which would cause Read-After-Write stalls. Hence, we take the AMR - * value from the check above. - */ - kuap_restore_amr(regs, amr); - - return ret; -} -#endif |