Subversion Repositories or1k_soc_on_altera_embedded_dev_kit

/* ptrace.c: Sparc process tracing support.

 *

 * Copyright (C) 1996 David S. Miller (davem@caipfs.rutgers.edu)

 *

 * Based upon code written by Ross Biro, Linus Torvalds, Bob Manson,

 * and David Mosberger.

 *

 * Added Linux support -miguel (weird, eh?, the original code was meant

 * to emulate SunOS).

 */

#include <linux/kernel.h>

#include <linux/sched.h>

#include <linux/mm.h>

#include <linux/errno.h>

#include <linux/ptrace.h>

#include <linux/user.h>

#include <linux/smp.h>

#include <linux/smp_lock.h>

#include <linux/security.h>

#include <linux/signal.h>

#include <asm/pgtable.h>

#include <asm/system.h>

#include <asm/uaccess.h>

#define MAGIC_CONSTANT 0x80000000

/* Returning from ptrace is a bit tricky because the syscall return

 * low level code assumes any value returned which is negative and

 * is a valid errno will mean setting the condition codes to indicate

 * an error return.  This doesn't work, so we have this hook.

 */

static inline void pt_error_return(struct pt_regs *regs, unsigned long error)

{

        regs->u_regs[UREG_I0] = error;

        regs->psr |= PSR_C;

        regs->pc = regs->npc;

        regs->npc += 4;

}

static inline void pt_succ_return(struct pt_regs *regs, unsigned long value)

{

        regs->u_regs[UREG_I0] = value;

        regs->psr &= ~PSR_C;

        regs->pc = regs->npc;

        regs->npc += 4;

}

static void

pt_succ_return_linux(struct pt_regs *regs, unsigned long value, long __user *addr)

{

        if (put_user(value, addr)) {

                pt_error_return(regs, EFAULT);

                return;

        }

        regs->u_regs[UREG_I0] = 0;

        regs->psr &= ~PSR_C;

        regs->pc = regs->npc;

        regs->npc += 4;

}

static void

pt_os_succ_return (struct pt_regs *regs, unsigned long val, long __user *addr)

{

        if (current->personality == PER_SUNOS)

                pt_succ_return (regs, val);

        else

                pt_succ_return_linux (regs, val, addr);

}

/* Fuck me gently with a chainsaw... */

static inline void read_sunos_user(struct pt_regs *regs, unsigned long offset,

                                   struct task_struct *tsk, long __user *addr)

{

        struct pt_regs *cregs = tsk->thread.kregs;

        struct thread_info *t = task_thread_info(tsk);

        int v;

        if(offset >= 1024)

                offset -= 1024; /* whee... */

        if(offset & ((sizeof(unsigned long) - 1))) {

                pt_error_return(regs, EIO);

                return;

        }

        if(offset >= 16 && offset < 784) {

                offset -= 16; offset >>= 2;

                pt_os_succ_return(regs, *(((unsigned long *)(&t->reg_window[0]))+offset), addr);

                return;

        }

        if(offset >= 784 && offset < 832) {

                offset -= 784; offset >>= 2;

                pt_os_succ_return(regs, *(((unsigned long *)(&t->rwbuf_stkptrs[0]))+offset), addr);

                return;

        }

        switch(offset) {

        case 0:

                v = t->ksp;

                break;

        case 4:

                v = t->kpc;

                break;

        case 8:

                v = t->kpsr;

                break;

        case 12:

                v = t->uwinmask;

                break;

        case 832:

                v = t->w_saved;

                break;

        case 896:

                v = cregs->u_regs[UREG_I0];

                break;

        case 900:

                v = cregs->u_regs[UREG_I1];

                break;

        case 904:

                v = cregs->u_regs[UREG_I2];

                break;

        case 908:

                v = cregs->u_regs[UREG_I3];

                break;

        case 912:

                v = cregs->u_regs[UREG_I4];

                break;

        case 916:

                v = cregs->u_regs[UREG_I5];

                break;

        case 920:

                v = cregs->u_regs[UREG_I6];

                break;

        case 924:

                if(tsk->thread.flags & MAGIC_CONSTANT)

                        v = cregs->u_regs[UREG_G1];

                else

                        v = 0;

                break;

        case 940:

                v = cregs->u_regs[UREG_I0];

                break;

        case 944:

                v = cregs->u_regs[UREG_I1];

                break;

        case 948:

                /* Isn't binary compatibility _fun_??? */

                if(cregs->psr & PSR_C)

                        v = cregs->u_regs[UREG_I0] << 24;

                else

                        v = 0;

                break;

                /* Rest of them are completely unsupported. */

        default:

                printk("%s [%d]: Wants to read user offset %ld\n",

                       current->comm, task_pid_nr(current), offset);

                pt_error_return(regs, EIO);

                return;

        }

        if (current->personality == PER_SUNOS)

                pt_succ_return (regs, v);

        else

                pt_succ_return_linux (regs, v, addr);

        return;

}

static inline void write_sunos_user(struct pt_regs *regs, unsigned long offset,

                                    struct task_struct *tsk)

{

        struct pt_regs *cregs = tsk->thread.kregs;

        struct thread_info *t = task_thread_info(tsk);

        unsigned long value = regs->u_regs[UREG_I3];

        if(offset >= 1024)

                offset -= 1024; /* whee... */

        if(offset & ((sizeof(unsigned long) - 1)))

                goto failure;

        if(offset >= 16 && offset < 784) {

                offset -= 16; offset >>= 2;

                *(((unsigned long *)(&t->reg_window[0]))+offset) = value;

                goto success;

        }

        if(offset >= 784 && offset < 832) {

                offset -= 784; offset >>= 2;

                *(((unsigned long *)(&t->rwbuf_stkptrs[0]))+offset) = value;

                goto success;

        }

        switch(offset) {

        case 896:

                cregs->u_regs[UREG_I0] = value;

                break;

        case 900:

                cregs->u_regs[UREG_I1] = value;

                break;

        case 904:

                cregs->u_regs[UREG_I2] = value;

                break;

        case 908:

                cregs->u_regs[UREG_I3] = value;

                break;

        case 912:

                cregs->u_regs[UREG_I4] = value;

                break;

        case 916:

                cregs->u_regs[UREG_I5] = value;

                break;

        case 920:

                cregs->u_regs[UREG_I6] = value;

                break;

        case 924:

                cregs->u_regs[UREG_I7] = value;

                break;

        case 940:

                cregs->u_regs[UREG_I0] = value;

                break;

        case 944:

                cregs->u_regs[UREG_I1] = value;

                break;

                /* Rest of them are completely unsupported or "no-touch". */

        default:

                printk("%s [%d]: Wants to write user offset %ld\n",

                       current->comm, task_pid_nr(current), offset);

                goto failure;

        }

success:

        pt_succ_return(regs, 0);

        return;

failure:

        pt_error_return(regs, EIO);

        return;

}

/* #define ALLOW_INIT_TRACING */

/* #define DEBUG_PTRACE */

#ifdef DEBUG_PTRACE

char *pt_rq [] = {

        /* 0  */ "TRACEME", "PEEKTEXT", "PEEKDATA", "PEEKUSR",

        /* 4  */ "POKETEXT", "POKEDATA", "POKEUSR", "CONT",

        /* 8  */ "KILL", "SINGLESTEP", "SUNATTACH", "SUNDETACH",

        /* 12 */ "GETREGS", "SETREGS", "GETFPREGS", "SETFPREGS",

        /* 16 */ "READDATA", "WRITEDATA", "READTEXT", "WRITETEXT",

        /* 20 */ "GETFPAREGS", "SETFPAREGS", "unknown", "unknown",

        /* 24 */ "SYSCALL", ""

};

#endif

/*

 * Called by kernel/ptrace.c when detaching..

 *

 * Make sure single step bits etc are not set.

 */

void ptrace_disable(struct task_struct *child)

{

        /* nothing to do */

}

asmlinkage void do_ptrace(struct pt_regs *regs)

{

        unsigned long request = regs->u_regs[UREG_I0];

        unsigned long pid = regs->u_regs[UREG_I1];

        unsigned long addr = regs->u_regs[UREG_I2];

        unsigned long data = regs->u_regs[UREG_I3];

        unsigned long addr2 = regs->u_regs[UREG_I4];

        struct task_struct *child;

        int ret;

        lock_kernel();

#ifdef DEBUG_PTRACE

        {

                char *s;

                if ((request >= 0) && (request <= 24))

                        s = pt_rq [request];

                else

                        s = "unknown";

                if (request == PTRACE_POKEDATA && data == 0x91d02001){

                        printk ("do_ptrace: breakpoint pid=%d, addr=%08lx addr2=%08lx\n",

                                pid, addr, addr2);

                } else

                        printk("do_ptrace: rq=%s(%d) pid=%d addr=%08lx data=%08lx addr2=%08lx\n",

                               s, (int) request, (int) pid, addr, data, addr2);

        }

#endif

        if (request == PTRACE_TRACEME) {

                ret = ptrace_traceme();

                if (ret < 0)

                        pt_error_return(regs, -ret);

                else

                        pt_succ_return(regs, 0);

                goto out;

        }

        child = ptrace_get_task_struct(pid);

        if (IS_ERR(child)) {

                ret = PTR_ERR(child);

                pt_error_return(regs, -ret);

                goto out;

        }

        if ((current->personality == PER_SUNOS && request == PTRACE_SUNATTACH)

            || (current->personality != PER_SUNOS && request == PTRACE_ATTACH)) {

                if (ptrace_attach(child)) {

                        pt_error_return(regs, EPERM);

                        goto out_tsk;

                }

                pt_succ_return(regs, 0);

                goto out_tsk;

        }

        ret = ptrace_check_attach(child, request == PTRACE_KILL);

        if (ret < 0) {

                pt_error_return(regs, -ret);

                goto out_tsk;

        }

        switch(request) {

        case PTRACE_PEEKTEXT: /* read word at location addr. */

        case PTRACE_PEEKDATA: {

                unsigned long tmp;

                if (access_process_vm(child, addr,

                                      &tmp, sizeof(tmp), 0) == sizeof(tmp))

                        pt_os_succ_return(regs, tmp, (long __user *)data);

                else

                        pt_error_return(regs, EIO);

                goto out_tsk;

        }

        case PTRACE_PEEKUSR:

                read_sunos_user(regs, addr, child, (long __user *) data);

                goto out_tsk;

        case PTRACE_POKEUSR:

                write_sunos_user(regs, addr, child);

                goto out_tsk;

        case PTRACE_POKETEXT: /* write the word at location addr. */

        case PTRACE_POKEDATA: {

                if (access_process_vm(child, addr,

                                      &data, sizeof(data), 1) == sizeof(data))

                        pt_succ_return(regs, 0);

                else

                        pt_error_return(regs, EIO);

                goto out_tsk;

        }

        case PTRACE_GETREGS: {

                struct pt_regs __user *pregs = (struct pt_regs __user *) addr;

                struct pt_regs *cregs = child->thread.kregs;

                int rval;

                if (!access_ok(VERIFY_WRITE, pregs, sizeof(struct pt_regs))) {

                        rval = -EFAULT;

                        pt_error_return(regs, -rval);

                        goto out_tsk;

                }

                __put_user(cregs->psr, (&pregs->psr));

                __put_user(cregs->pc, (&pregs->pc));

                __put_user(cregs->npc, (&pregs->npc));

                __put_user(cregs->y, (&pregs->y));

                for(rval = 1; rval < 16; rval++)

                        __put_user(cregs->u_regs[rval], (&pregs->u_regs[rval - 1]));

                pt_succ_return(regs, 0);

#ifdef DEBUG_PTRACE

                printk ("PC=%x nPC=%x o7=%x\n", cregs->pc, cregs->npc, cregs->u_regs [15]);

#endif

                goto out_tsk;

        }

        case PTRACE_SETREGS: {

                struct pt_regs __user *pregs = (struct pt_regs __user *) addr;

                struct pt_regs *cregs = child->thread.kregs;

                unsigned long psr, pc, npc, y;

                int i;

                /* Must be careful, tracing process can only set certain

                 * bits in the psr.

                 */

                if (!access_ok(VERIFY_READ, pregs, sizeof(struct pt_regs))) {

                        pt_error_return(regs, EFAULT);

                        goto out_tsk;

                }

                __get_user(psr, (&pregs->psr));

                __get_user(pc, (&pregs->pc));

                __get_user(npc, (&pregs->npc));

                __get_user(y, (&pregs->y));

                psr &= PSR_ICC;

                cregs->psr &= ~PSR_ICC;

                cregs->psr |= psr;

                if (!((pc | npc) & 3)) {

                        cregs->pc = pc;

                        cregs->npc =npc;

                }

                cregs->y = y;

                for(i = 1; i < 16; i++)

                        __get_user(cregs->u_regs[i], (&pregs->u_regs[i-1]));

                pt_succ_return(regs, 0);

                goto out_tsk;

        }

        case PTRACE_GETFPREGS: {

                struct fps {

                        unsigned long regs[32];

                        unsigned long fsr;

                        unsigned long flags;

                        unsigned long extra;

                        unsigned long fpqd;

                        struct fq {

                                unsigned long *insnaddr;

                                unsigned long insn;

                        } fpq[16];

                };

                struct fps __user *fps = (struct fps __user *) addr;

                int i;

                if (!access_ok(VERIFY_WRITE, fps, sizeof(struct fps))) {

                        i = -EFAULT;

                        pt_error_return(regs, -i);

                        goto out_tsk;

                }

                for(i = 0; i < 32; i++)

                        __put_user(child->thread.float_regs[i], (&fps->regs[i]));

                __put_user(child->thread.fsr, (&fps->fsr));

                __put_user(child->thread.fpqdepth, (&fps->fpqd));

                __put_user(0, (&fps->flags));

                __put_user(0, (&fps->extra));

                for(i = 0; i < 16; i++) {

                        __put_user(child->thread.fpqueue[i].insn_addr,

                                   (&fps->fpq[i].insnaddr));

                        __put_user(child->thread.fpqueue[i].insn, (&fps->fpq[i].insn));

                }

                pt_succ_return(regs, 0);

                goto out_tsk;

        }

        case PTRACE_SETFPREGS: {

                struct fps {

                        unsigned long regs[32];

                        unsigned long fsr;

                        unsigned long flags;

                        unsigned long extra;

                        unsigned long fpqd;

                        struct fq {

                                unsigned long *insnaddr;

                                unsigned long insn;

                        } fpq[16];

                };

                struct fps __user *fps = (struct fps __user *) addr;

                int i;

                if (!access_ok(VERIFY_READ, fps, sizeof(struct fps))) {

                        i = -EFAULT;

                        pt_error_return(regs, -i);

                        goto out_tsk;

                }

                copy_from_user(&child->thread.float_regs[0], &fps->regs[0], (32 * sizeof(unsigned long)));

                __get_user(child->thread.fsr, (&fps->fsr));

                __get_user(child->thread.fpqdepth, (&fps->fpqd));

                for(i = 0; i < 16; i++) {

                        __get_user(child->thread.fpqueue[i].insn_addr,

                                   (&fps->fpq[i].insnaddr));

                        __get_user(child->thread.fpqueue[i].insn, (&fps->fpq[i].insn));

                }

                pt_succ_return(regs, 0);

                goto out_tsk;

        }

        case PTRACE_READTEXT:

        case PTRACE_READDATA: {

                int res = ptrace_readdata(child, addr,

                                          (void __user *) addr2, data);

                if (res == data) {

                        pt_succ_return(regs, 0);

                        goto out_tsk;

                }

                /* Partial read is an IO failure */

                if (res >= 0)

                        res = -EIO;

                pt_error_return(regs, -res);

                goto out_tsk;

        }

        case PTRACE_WRITETEXT:

        case PTRACE_WRITEDATA: {

                int res = ptrace_writedata(child, (void __user *) addr2,

                                           addr, data);

                if (res == data) {

                        pt_succ_return(regs, 0);

                        goto out_tsk;

                }

                /* Partial write is an IO failure */

                if (res >= 0)

                        res = -EIO;

                pt_error_return(regs, -res);

                goto out_tsk;

        }

        case PTRACE_SYSCALL: /* continue and stop at (return from) syscall */

                addr = 1;

        case PTRACE_CONT: { /* restart after signal. */

                if (!valid_signal(data)) {

                        pt_error_return(regs, EIO);

                        goto out_tsk;

                }

                if (request == PTRACE_SYSCALL)

                        set_tsk_thread_flag(child, TIF_SYSCALL_TRACE);

                else

                        clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);

                child->exit_code = data;

#ifdef DEBUG_PTRACE

                printk("CONT: %s [%d]: set exit_code = %x %lx %lx\n",

                        child->comm, child->pid, child->exit_code,

                        child->thread.kregs->pc,

                        child->thread.kregs->npc);

#endif

                wake_up_process(child);

                pt_succ_return(regs, 0);

                goto out_tsk;

        }

/*

 * make the child exit.  Best I can do is send it a sigkill.

 * perhaps it should be put in the status that it wants to

 * exit.

 */

        case PTRACE_KILL: {

                if (child->exit_state == EXIT_ZOMBIE) { /* already dead */

                        pt_succ_return(regs, 0);

                        goto out_tsk;

                }

                wake_up_process(child);

                child->exit_code = SIGKILL;

                pt_succ_return(regs, 0);

                goto out_tsk;

        }

        case PTRACE_SUNDETACH: { /* detach a process that was attached. */

                int err = ptrace_detach(child, data);

                if (err) {

                        pt_error_return(regs, EIO);

                        goto out_tsk;

                }

                pt_succ_return(regs, 0);

                goto out_tsk;

        }

        /* PTRACE_DUMPCORE unsupported... */

        default: {

                int err = ptrace_request(child, request, addr, data);

                if (err)

                        pt_error_return(regs, -err);

                else

                        pt_succ_return(regs, 0);

                goto out_tsk;

        }

        }

out_tsk:

        if (child)

                put_task_struct(child);

out:

        unlock_kernel();

}

asmlinkage void syscall_trace(void)

{

#ifdef DEBUG_PTRACE

        printk("%s [%d]: syscall_trace\n", current->comm, current->pid);

#endif

        if (!test_thread_flag(TIF_SYSCALL_TRACE))

                return;

        if (!(current->ptrace & PT_PTRACED))

                return;

        current->thread.flags ^= MAGIC_CONSTANT;

        ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD)

                                 ? 0x80 : 0));

        /*

         * this isn't the same as continuing with a signal, but it will do

         * for normal use.  strace only continues with a signal if the

         * stopping signal is not SIGTRAP.  -brl

         */

#ifdef DEBUG_PTRACE

        printk("%s [%d]: syscall_trace exit= %x\n", current->comm,

                current->pid, current->exit_code);

#endif

        if (current->exit_code) {

                send_sig (current->exit_code, current, 1);

                current->exit_code = 0;

        }

}