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Release 4.14 arch/sh/kernel/process_64.c

Directory: arch/sh/kernel
/*
 * arch/sh/kernel/process_64.c
 *
 * This file handles the architecture-dependent parts of process handling..
 *
 * Copyright (C) 2000, 2001  Paolo Alberelli
 * Copyright (C) 2003 - 2007  Paul Mundt
 * Copyright (C) 2003, 2004 Richard Curnow
 *
 * Started from SH3/4 version:
 *   Copyright (C) 1999, 2000  Niibe Yutaka & Kaz Kojima
 *
 *   In turn started from i386 version:
 *     Copyright (C) 1995  Linus Torvalds
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 */
#include <linux/mm.h>
#include <linux/fs.h>
#include <linux/ptrace.h>
#include <linux/reboot.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/io.h>
#include <linux/sched/debug.h>
#include <linux/sched/task.h>
#include <linux/sched/task_stack.h>
#include <asm/syscalls.h>
#include <linux/uaccess.h>
#include <asm/pgtable.h>
#include <asm/mmu_context.h>
#include <asm/fpu.h>
#include <asm/switch_to.h>


struct task_struct *last_task_used_math = NULL;

struct pt_regs fake_swapper_regs = { 0, };


void show_regs(struct pt_regs *regs) { unsigned long long ah, al, bh, bl, ch, cl; printk("\n"); show_regs_print_info(KERN_DEFAULT); ah = (regs->pc) >> 32; al = (regs->pc) & 0xffffffff; bh = (regs->regs[18]) >> 32; bl = (regs->regs[18]) & 0xffffffff; ch = (regs->regs[15]) >> 32; cl = (regs->regs[15]) & 0xffffffff; printk("PC : %08Lx%08Lx LINK: %08Lx%08Lx SP : %08Lx%08Lx\n", ah, al, bh, bl, ch, cl); ah = (regs->sr) >> 32; al = (regs->sr) & 0xffffffff; asm volatile ("getcon " __TEA ", %0" : "=r" (bh)); asm volatile ("getcon " __TEA ", %0" : "=r" (bl)); bh = (bh) >> 32; bl = (bl) & 0xffffffff; asm volatile ("getcon " __KCR0 ", %0" : "=r" (ch)); asm volatile ("getcon " __KCR0 ", %0" : "=r" (cl)); ch = (ch) >> 32; cl = (cl) & 0xffffffff; printk("SR : %08Lx%08Lx TEA : %08Lx%08Lx KCR0: %08Lx%08Lx\n", ah, al, bh, bl, ch, cl); ah = (regs->regs[0]) >> 32; al = (regs->regs[0]) & 0xffffffff; bh = (regs->regs[1]) >> 32; bl = (regs->regs[1]) & 0xffffffff; ch = (regs->regs[2]) >> 32; cl = (regs->regs[2]) & 0xffffffff; printk("R0 : %08Lx%08Lx R1 : %08Lx%08Lx R2 : %08Lx%08Lx\n", ah, al, bh, bl, ch, cl); ah = (regs->regs[3]) >> 32; al = (regs->regs[3]) & 0xffffffff; bh = (regs->regs[4]) >> 32; bl = (regs->regs[4]) & 0xffffffff; ch = (regs->regs[5]) >> 32; cl = (regs->regs[5]) & 0xffffffff; printk("R3 : %08Lx%08Lx R4 : %08Lx%08Lx R5 : %08Lx%08Lx\n", ah, al, bh, bl, ch, cl); ah = (regs->regs[6]) >> 32; al = (regs->regs[6]) & 0xffffffff; bh = (regs->regs[7]) >> 32; bl = (regs->regs[7]) & 0xffffffff; ch = (regs->regs[8]) >> 32; cl = (regs->regs[8]) & 0xffffffff; printk("R6 : %08Lx%08Lx R7 : %08Lx%08Lx R8 : %08Lx%08Lx\n", ah, al, bh, bl, ch, cl); ah = (regs->regs[9]) >> 32; al = (regs->regs[9]) & 0xffffffff; bh = (regs->regs[10]) >> 32; bl = (regs->regs[10]) & 0xffffffff; ch = (regs->regs[11]) >> 32; cl = (regs->regs[11]) & 0xffffffff; printk("R9 : %08Lx%08Lx R10 : %08Lx%08Lx R11 : %08Lx%08Lx\n", ah, al, bh, bl, ch, cl); ah = (regs->regs[12]) >> 32; al = (regs->regs[12]) & 0xffffffff; bh = (regs->regs[13]) >> 32; bl = (regs->regs[13]) & 0xffffffff; ch = (regs->regs[14]) >> 32; cl = (regs->regs[14]) & 0xffffffff; printk("R12 : %08Lx%08Lx R13 : %08Lx%08Lx R14 : %08Lx%08Lx\n", ah, al, bh, bl, ch, cl); ah = (regs->regs[16]) >> 32; al = (regs->regs[16]) & 0xffffffff; bh = (regs->regs[17]) >> 32; bl = (regs->regs[17]) & 0xffffffff; ch = (regs->regs[19]) >> 32; cl = (regs->regs[19]) & 0xffffffff; printk("R16 : %08Lx%08Lx R17 : %08Lx%08Lx R19 : %08Lx%08Lx\n", ah, al, bh, bl, ch, cl); ah = (regs->regs[20]) >> 32; al = (regs->regs[20]) & 0xffffffff; bh = (regs->regs[21]) >> 32; bl = (regs->regs[21]) & 0xffffffff; ch = (regs->regs[22]) >> 32; cl = (regs->regs[22]) & 0xffffffff; printk("R20 : %08Lx%08Lx R21 : %08Lx%08Lx R22 : %08Lx%08Lx\n", ah, al, bh, bl, ch, cl); ah = (regs->regs[23]) >> 32; al = (regs->regs[23]) & 0xffffffff; bh = (regs->regs[24]) >> 32; bl = (regs->regs[24]) & 0xffffffff; ch = (regs->regs[25]) >> 32; cl = (regs->regs[25]) & 0xffffffff; printk("R23 : %08Lx%08Lx R24 : %08Lx%08Lx R25 : %08Lx%08Lx\n", ah, al, bh, bl, ch, cl); ah = (regs->regs[26]) >> 32; al = (regs->regs[26]) & 0xffffffff; bh = (regs->regs[27]) >> 32; bl = (regs->regs[27]) & 0xffffffff; ch = (regs->regs[28]) >> 32; cl = (regs->regs[28]) & 0xffffffff; printk("R26 : %08Lx%08Lx R27 : %08Lx%08Lx R28 : %08Lx%08Lx\n", ah, al, bh, bl, ch, cl); ah = (regs->regs[29]) >> 32; al = (regs->regs[29]) & 0xffffffff; bh = (regs->regs[30]) >> 32; bl = (regs->regs[30]) & 0xffffffff; ch = (regs->regs[31]) >> 32; cl = (regs->regs[31]) & 0xffffffff; printk("R29 : %08Lx%08Lx R30 : %08Lx%08Lx R31 : %08Lx%08Lx\n", ah, al, bh, bl, ch, cl); ah = (regs->regs[32]) >> 32; al = (regs->regs[32]) & 0xffffffff; bh = (regs->regs[33]) >> 32; bl = (regs->regs[33]) & 0xffffffff; ch = (regs->regs[34]) >> 32; cl = (regs->regs[34]) & 0xffffffff; printk("R32 : %08Lx%08Lx R33 : %08Lx%08Lx R34 : %08Lx%08Lx\n", ah, al, bh, bl, ch, cl); ah = (regs->regs[35]) >> 32; al = (regs->regs[35]) & 0xffffffff; bh = (regs->regs[36]) >> 32; bl = (regs->regs[36]) & 0xffffffff; ch = (regs->regs[37]) >> 32; cl = (regs->regs[37]) & 0xffffffff; printk("R35 : %08Lx%08Lx R36 : %08Lx%08Lx R37 : %08Lx%08Lx\n", ah, al, bh, bl, ch, cl); ah = (regs->regs[38]) >> 32; al = (regs->regs[38]) & 0xffffffff; bh = (regs->regs[39]) >> 32; bl = (regs->regs[39]) & 0xffffffff; ch = (regs->regs[40]) >> 32; cl = (regs->regs[40]) & 0xffffffff; printk("R38 : %08Lx%08Lx R39 : %08Lx%08Lx R40 : %08Lx%08Lx\n", ah, al, bh, bl, ch, cl); ah = (regs->regs[41]) >> 32; al = (regs->regs[41]) & 0xffffffff; bh = (regs->regs[42]) >> 32; bl = (regs->regs[42]) & 0xffffffff; ch = (regs->regs[43]) >> 32; cl = (regs->regs[43]) & 0xffffffff; printk("R41 : %08Lx%08Lx R42 : %08Lx%08Lx R43 : %08Lx%08Lx\n", ah, al, bh, bl, ch, cl); ah = (regs->regs[44]) >> 32; al = (regs->regs[44]) & 0xffffffff; bh = (regs->regs[45]) >> 32; bl = (regs->regs[45]) & 0xffffffff; ch = (regs->regs[46]) >> 32; cl = (regs->regs[46]) & 0xffffffff; printk("R44 : %08Lx%08Lx R45 : %08Lx%08Lx R46 : %08Lx%08Lx\n", ah, al, bh, bl, ch, cl); ah = (regs->regs[47]) >> 32; al = (regs->regs[47]) & 0xffffffff; bh = (regs->regs[48]) >> 32; bl = (regs->regs[48]) & 0xffffffff; ch = (regs->regs[49]) >> 32; cl = (regs->regs[49]) & 0xffffffff; printk("R47 : %08Lx%08Lx R48 : %08Lx%08Lx R49 : %08Lx%08Lx\n", ah, al, bh, bl, ch, cl); ah = (regs->regs[50]) >> 32; al = (regs->regs[50]) & 0xffffffff; bh = (regs->regs[51]) >> 32; bl = (regs->regs[51]) & 0xffffffff; ch = (regs->regs[52]) >> 32; cl = (regs->regs[52]) & 0xffffffff; printk("R50 : %08Lx%08Lx R51 : %08Lx%08Lx R52 : %08Lx%08Lx\n", ah, al, bh, bl, ch, cl); ah = (regs->regs[53]) >> 32; al = (regs->regs[53]) & 0xffffffff; bh = (regs->regs[54]) >> 32; bl = (regs->regs[54]) & 0xffffffff; ch = (regs->regs[55]) >> 32; cl = (regs->regs[55]) & 0xffffffff; printk("R53 : %08Lx%08Lx R54 : %08Lx%08Lx R55 : %08Lx%08Lx\n", ah, al, bh, bl, ch, cl); ah = (regs->regs[56]) >> 32; al = (regs->regs[56]) & 0xffffffff; bh = (regs->regs[57]) >> 32; bl = (regs->regs[57]) & 0xffffffff; ch = (regs->regs[58]) >> 32; cl = (regs->regs[58]) & 0xffffffff; printk("R56 : %08Lx%08Lx R57 : %08Lx%08Lx R58 : %08Lx%08Lx\n", ah, al, bh, bl, ch, cl); ah = (regs->regs[59]) >> 32; al = (regs->regs[59]) & 0xffffffff; bh = (regs->regs[60]) >> 32; bl = (regs->regs[60]) & 0xffffffff; ch = (regs->regs[61]) >> 32; cl = (regs->regs[61]) & 0xffffffff; printk("R59 : %08Lx%08Lx R60 : %08Lx%08Lx R61 : %08Lx%08Lx\n", ah, al, bh, bl, ch, cl); ah = (regs->regs[62]) >> 32; al = (regs->regs[62]) & 0xffffffff; bh = (regs->tregs[0]) >> 32; bl = (regs->tregs[0]) & 0xffffffff; ch = (regs->tregs[1]) >> 32; cl = (regs->tregs[1]) & 0xffffffff; printk("R62 : %08Lx%08Lx T0 : %08Lx%08Lx T1 : %08Lx%08Lx\n", ah, al, bh, bl, ch, cl); ah = (regs->tregs[2]) >> 32; al = (regs->tregs[2]) & 0xffffffff; bh = (regs->tregs[3]) >> 32; bl = (regs->tregs[3]) & 0xffffffff; ch = (regs->tregs[4]) >> 32; cl = (regs->tregs[4]) & 0xffffffff; printk("T2 : %08Lx%08Lx T3 : %08Lx%08Lx T4 : %08Lx%08Lx\n", ah, al, bh, bl, ch, cl); ah = (regs->tregs[5]) >> 32; al = (regs->tregs[5]) & 0xffffffff; bh = (regs->tregs[6]) >> 32; bl = (regs->tregs[6]) & 0xffffffff; ch = (regs->tregs[7]) >> 32; cl = (regs->tregs[7]) & 0xffffffff; printk("T5 : %08Lx%08Lx T6 : %08Lx%08Lx T7 : %08Lx%08Lx\n", ah, al, bh, bl, ch, cl); /* * If we're in kernel mode, dump the stack too.. */ if (!user_mode(regs)) { void show_stack(struct task_struct *tsk, unsigned long *sp); unsigned long sp = regs->regs[15] & 0xffffffff; struct task_struct *tsk = get_current(); tsk->thread.kregs = regs; show_stack(tsk, (unsigned long *)sp); } }

Contributors

PersonTokensPropCommitsCommitProp
Paul Mundt245199.80%150.00%
Tejun Heo50.20%150.00%
Total2456100.00%2100.00%

/* * Free current thread data structures etc.. */
void exit_thread(struct task_struct *tsk) { /* * See arch/sparc/kernel/process.c for the precedent for doing * this -- RPC. * * The SH-5 FPU save/restore approach relies on * last_task_used_math pointing to a live task_struct. When * another task tries to use the FPU for the 1st time, the FPUDIS * trap handling (see arch/sh/kernel/cpu/sh5/fpu.c) will save the * existing FPU state to the FP regs field within * last_task_used_math before re-loading the new task's FPU state * (or initialising it if the FPU has been used before). So if * last_task_used_math is stale, and its page has already been * re-allocated for another use, the consequences are rather * grim. Unless we null it here, there is no other path through * which it would get safely nulled. */ #ifdef CONFIG_SH_FPU if (last_task_used_math == tsk) last_task_used_math = NULL; #endif }

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PersonTokensPropCommitsCommitProp
Paul Mundt2180.77%375.00%
Jiri Slaby519.23%125.00%
Total26100.00%4100.00%


void flush_thread(void) { /* Called by fs/exec.c (setup_new_exec) to remove traces of a * previously running executable. */ #ifdef CONFIG_SH_FPU if (last_task_used_math == current) { last_task_used_math = NULL; } /* Force FPU state to be reinitialised after exec */ clear_used_math(); #endif /* if we are a kernel thread, about to change to user thread, * update kreg */ if(current->thread.kregs==&fake_swapper_regs) { current->thread.kregs = ((struct pt_regs *)(THREAD_SIZE + (unsigned long) current) - 1); current->thread.uregs = current->thread.kregs; } }

Contributors

PersonTokensPropCommitsCommitProp
Paul Mundt7796.25%250.00%
Andrea Arcangeli22.50%125.00%
Linus Torvalds11.25%125.00%
Total80100.00%4100.00%


void release_thread(struct task_struct *dead_task) { /* do nothing */ }

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PersonTokensPropCommitsCommitProp
Paul Mundt11100.00%1100.00%
Total11100.00%1100.00%

/* Fill in the fpu structure for a core dump.. */
int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpu) { #ifdef CONFIG_SH_FPU int fpvalid; struct task_struct *tsk = current; fpvalid = !!tsk_used_math(tsk); if (fpvalid) { if (current == last_task_used_math) { enable_fpu(); save_fpu(tsk); disable_fpu(); last_task_used_math = 0; regs->sr |= SR_FD; } memcpy(fpu, &tsk->thread.xstate->hardfpu, sizeof(*fpu)); } return fpvalid; #else return 0; /* Task didn't use the fpu at all. */ #endif }

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Paul Mundt9795.10%583.33%
Andrea Arcangeli54.90%116.67%
Total102100.00%6100.00%

EXPORT_SYMBOL(dump_fpu); asmlinkage void ret_from_fork(void); asmlinkage void ret_from_kernel_thread(void);
int copy_thread(unsigned long clone_flags, unsigned long usp, unsigned long arg, struct task_struct *p) { struct pt_regs *childregs; #ifdef CONFIG_SH_FPU /* can't happen for a kernel thread */ if (last_task_used_math == current) { enable_fpu(); save_fpu(current); disable_fpu(); last_task_used_math = NULL; current_pt_regs()->sr |= SR_FD; } #endif /* Copy from sh version */ childregs = (struct pt_regs *)(THREAD_SIZE + task_stack_page(p)) - 1; p->thread.sp = (unsigned long) childregs; if (unlikely(p->flags & PF_KTHREAD)) { memset(childregs, 0, sizeof(struct pt_regs)); childregs->regs[2] = (unsigned long)arg; childregs->regs[3] = (unsigned long)usp; childregs->sr = (1 << 30); /* not user_mode */ childregs->sr |= SR_FD; /* Invalidate FPU flag */ p->thread.pc = (unsigned long) ret_from_kernel_thread; return 0; } *childregs = *current_pt_regs(); /* * Sign extend the edited stack. * Note that thread.pc and thread.pc will stay * 32-bit wide and context switch must take care * of NEFF sign extension. */ if (usp) childregs->regs[15] = neff_sign_extend(usp); p->thread.uregs = childregs; childregs->regs[9] = 0; /* Set return value for child */ childregs->sr |= SR_FD; /* Invalidate FPU flag */ p->thread.pc = (unsigned long) ret_from_fork; return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Paul Mundt14057.61%555.56%
Al Viro10241.98%333.33%
Chen Gang S10.41%111.11%
Total243100.00%9100.00%

#ifdef CONFIG_FRAME_POINTER
static int in_sh64_switch_to(unsigned long pc) { extern char __sh64_switch_to_end; /* For a sleeping task, the PC is somewhere in the middle of the function, so we don't have to worry about masking the LSB off */ return (pc >= (unsigned long) sh64_switch_to) && (pc < (unsigned long) &__sh64_switch_to_end); }

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PersonTokensPropCommitsCommitProp
Paul Mundt37100.00%1100.00%
Total37100.00%1100.00%

#endif
unsigned long get_wchan(struct task_struct *p) { unsigned long pc; if (!p || p == current || p->state == TASK_RUNNING) return 0; /* * The same comment as on the Alpha applies here, too ... */ pc = thread_saved_pc(p); #ifdef CONFIG_FRAME_POINTER if (in_sh64_switch_to(pc)) { unsigned long schedule_fp; unsigned long sh64_switch_to_fp; unsigned long schedule_caller_pc; sh64_switch_to_fp = (long) p->thread.sp; /* r14 is saved at offset 4 in the sh64_switch_to frame */ schedule_fp = *(unsigned long *) (long)(sh64_switch_to_fp + 4); /* and the caller of 'schedule' is (currently!) saved at offset 24 in the frame of schedule (from disasm) */ schedule_caller_pc = *(unsigned long *) (long)(schedule_fp + 24); return schedule_caller_pc; } #endif return pc; }

Contributors

PersonTokensPropCommitsCommitProp
Paul Mundt11898.33%266.67%
Valdis Kletnieks21.67%133.33%
Total120100.00%3100.00%


Overall Contributors

PersonTokensPropCommitsCommitProp
Paul Mundt301095.01%1546.88%
Al Viro1093.44%39.38%
Arnd Bergmann90.28%13.12%
Ingo Molnar90.28%39.38%
Tejun Heo80.25%26.25%
Andrea Arcangeli70.22%13.12%
Jiri Slaby50.16%13.12%
David Howells30.09%13.12%
Adrian Bunk30.09%13.12%
Linus Torvalds20.06%26.25%
Valdis Kletnieks20.06%13.12%
Chen Gang S10.03%13.12%
Total3168100.00%32100.00%
Directory: arch/sh/kernel
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