Something went wrong. Try again.
Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Something went wrong. Try again.
123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246// SPDX-License-Identifier: GPL-2.0/* * This file handles the architecture dependent parts of process handling. * * Copyright IBM Corp. 1999, 2009 * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>, * Hartmut Penner <hp@de.ibm.com>, * Denis Joseph Barrow, */
#include <linux/elf-randomize.h>#include <linux/compiler.h>#include <linux/cpu.h>#include <linux/sched.h>#include <linux/sched/debug.h>#include <linux/sched/task.h>#include <linux/sched/task_stack.h>#include <linux/kernel.h>#include <linux/mm.h>#include <linux/elfcore.h>#include <linux/smp.h>#include <linux/slab.h>#include <linux/interrupt.h>#include <linux/tick.h>#include <linux/personality.h>#include <linux/syscalls.h>#include <linux/kprobes.h>#include <linux/random.h>#include <linux/init_task.h>#include <linux/entry-common.h>#include <linux/io.h>#include <asm/guarded_storage.h>#include <asm/access-regs.h>#include <asm/switch_to.h>#include <asm/cpu_mf.h>#include <asm/processor.h>#include <asm/ptrace.h>#include <asm/vtimer.h>#include <asm/exec.h>#include <asm/fpu.h>#include <asm/irq.h>#include <asm/nmi.h>#include <asm/smp.h>#include <asm/stacktrace.h>#include <asm/runtime_instr.h>#include <asm/unwind.h>#include "entry.h"
void ret_from_fork(void) asm("ret_from_fork");
void __ret_from_fork(struct task_struct *prev, struct pt_regs *regs){ int (*func)(void *arg);
schedule_tail(prev);
if (!user_mode(regs)) { /* Kernel thread */ func = (void *)regs->gprs[9]; func((void *)regs->gprs[10]); } clear_pt_regs_flag(regs, PIF_SYSCALL); syscall_exit_to_user_mode(regs);}
void flush_thread(void){}
void arch_setup_new_exec(void){ if (get_lowcore()->current_pid != current->pid) { get_lowcore()->current_pid = current->pid; if (test_facility(40)) lpp(&get_lowcore()->lpp); }}
void arch_release_task_struct(struct task_struct *tsk){ runtime_instr_release(tsk); guarded_storage_release(tsk);}
int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src){ save_user_fpu_regs();
*dst = *src; dst->thread.kfpu_flags = 0;
/* * Don't transfer over the runtime instrumentation or the guarded * storage control block pointers. These fields are cleared here instead * of in copy_thread() to avoid premature freeing of associated memory * on fork() failure. Wait to clear the RI flag because ->stack still * refers to the source thread. */ dst->thread.ri_cb = NULL; dst->thread.gs_cb = NULL; dst->thread.gs_bc_cb = NULL;
return 0;}
int copy_thread(struct task_struct *p, const struct kernel_clone_args *args){ u64 clone_flags = args->flags; unsigned long new_stackp = args->stack; unsigned long tls = args->tls; struct fake_frame { struct stack_frame sf; struct pt_regs childregs; } *frame;
frame = container_of(task_pt_regs(p), struct fake_frame, childregs); p->thread.ksp = (unsigned long) frame; /* Save access registers to new thread structure. */ save_access_regs(&p->thread.acrs[0]); /* start new process with ar4 pointing to the correct address space */ /* Don't copy debug registers */ memset(&p->thread.per_user, 0, sizeof(p->thread.per_user)); memset(&p->thread.per_event, 0, sizeof(p->thread.per_event)); clear_tsk_thread_flag(p, TIF_SINGLE_STEP); p->thread.per_flags = 0; /* Initialize per thread user and system timer values */ p->thread.user_timer = 0; p->thread.guest_timer = 0; p->thread.system_timer = 0; p->thread.hardirq_timer = 0; p->thread.softirq_timer = 0; p->thread.last_break = 1;
frame->sf.back_chain = 0; frame->sf.gprs[11 - 6] = (unsigned long)&frame->childregs; frame->sf.gprs[12 - 6] = (unsigned long)p; /* new return point is ret_from_fork */ frame->sf.gprs[14 - 6] = (unsigned long)ret_from_fork; /* fake return stack for resume(), don't go back to schedule */ frame->sf.gprs[15 - 6] = (unsigned long)frame;
/* Store access registers to kernel stack of new process. */ if (unlikely(args->fn)) { /* kernel thread */ memset(&frame->childregs, 0, sizeof(struct pt_regs)); frame->childregs.psw.mask = PSW_KERNEL_BITS | PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK; frame->childregs.gprs[9] = (unsigned long)args->fn; frame->childregs.gprs[10] = (unsigned long)args->fn_arg; frame->childregs.orig_gpr2 = -1; frame->childregs.last_break = 1; return 0; } frame->childregs = *current_pt_regs(); frame->childregs.gprs[2] = 0; /* child returns 0 on fork. */ frame->childregs.flags = 0; if (new_stackp) frame->childregs.gprs[15] = new_stackp; /* * Clear the runtime instrumentation flag after the above childregs * copy. The CB pointer was already cleared in arch_dup_task_struct(). */ frame->childregs.psw.mask &= ~PSW_MASK_RI;
/* Set a new TLS ? */ if (clone_flags & CLONE_SETTLS) { p->thread.acrs[0] = (unsigned int)(tls >> 32); p->thread.acrs[1] = (unsigned int)tls; } /* * s390 stores the svc return address in arch_data when calling * sigreturn()/restart_syscall() via vdso. 1 means no valid address * stored. */ p->restart_block.arch_data = 1; return 0;}
void execve_tail(void){ current->thread.ufpu.fpc = 0; fpu_sfpc(0);}
struct task_struct *__switch_to(struct task_struct *prev, struct task_struct *next){ save_user_fpu_regs(); save_kernel_fpu_regs(&prev->thread); save_access_regs(&prev->thread.acrs[0]); save_ri_cb(prev->thread.ri_cb); save_gs_cb(prev->thread.gs_cb); update_cr_regs(next); restore_kernel_fpu_regs(&next->thread); restore_access_regs(&next->thread.acrs[0]); restore_ri_cb(next->thread.ri_cb, prev->thread.ri_cb); restore_gs_cb(next->thread.gs_cb); return __switch_to_asm(prev, next);}
unsigned long __get_wchan(struct task_struct *p){ struct unwind_state state; unsigned long ip = 0;
if (!try_get_task_stack(p)) return 0;
unwind_for_each_frame(&state, p, NULL, 0) { if (state.stack_info.type != STACK_TYPE_TASK) { ip = 0; break; }
ip = unwind_get_return_address(&state); if (!ip) break;
if (!in_sched_functions(ip)) break; }
put_task_stack(p); return ip;}
unsigned long arch_align_stack(unsigned long sp){ if (!(current->personality & ADDR_NO_RANDOMIZE) && randomize_va_space) sp -= get_random_u32_below(PAGE_SIZE); return sp & ~0xf;}
static inline unsigned long brk_rnd(void){ return (get_random_u16() & BRK_RND_MASK) << PAGE_SHIFT;}
unsigned long arch_randomize_brk(struct mm_struct *mm){ unsigned long ret;
ret = PAGE_ALIGN(mm->brk + brk_rnd()); return (ret > mm->brk) ? ret : mm->brk;}