Commit 4a3b9893 authored by David Howells's avatar David Howells Committed by Linus Torvalds
Browse files

FRV: Implement new-style ptrace



Implement the new-style ptrace for FRV, including adding appropriate
tracehooks.
Signed-off-by: default avatarDavid Howells <dhowells@redhat.com>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 24ceb7e8
......@@ -6,6 +6,7 @@ config FRV
bool
default y
select HAVE_IDE
select HAVE_ARCH_TRACEHOOK
config ZONE_DMA
bool
......
......@@ -116,6 +116,7 @@ do { \
} while(0)
#define USE_ELF_CORE_DUMP
#define CORE_DUMP_USE_REGSET
#define ELF_FDPIC_CORE_EFLAGS EF_FRV_FDPIC
#define ELF_EXEC_PAGESIZE 16384
......
......@@ -65,6 +65,8 @@
#ifdef __KERNEL__
#ifndef __ASSEMBLY__
struct task_struct;
/*
* we dedicate GR28 to keeping a pointer to the current exception frame
* - gr28 is destroyed on entry to the kernel from userspace
......@@ -73,11 +75,18 @@ register struct pt_regs *__frame asm("gr28");
#define user_mode(regs) (!((regs)->psr & PSR_S))
#define instruction_pointer(regs) ((regs)->pc)
#define user_stack_pointer(regs) ((regs)->sp)
extern unsigned long user_stack(const struct pt_regs *);
extern void show_regs(struct pt_regs *);
#define profile_pc(regs) ((regs)->pc)
#endif
#define task_pt_regs(task) ((task)->thread.frame0)
#define arch_has_single_step() (1)
extern void user_enable_single_step(struct task_struct *);
extern void user_disable_single_step(struct task_struct *);
#endif /* !__ASSEMBLY__ */
#endif /* __KERNEL__ */
#endif /* _ASM_PTRACE_H */
/* syscall parameter access functions
*
* Copyright (C) 2009 Red Hat, Inc. All Rights Reserved.
* Written by David Howells (dhowells@redhat.com)
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public Licence
* as published by the Free Software Foundation; either version
* 2 of the Licence, or (at your option) any later version.
*/
#ifndef _ASM_SYSCALL_H
#define _ASM_SYSCALL_H
#include <linux/err.h>
#include <asm/ptrace.h>
/*
* Get the system call number or -1
*/
static inline long syscall_get_nr(struct task_struct *task,
struct pt_regs *regs)
{
return regs->syscallno;
}
/*
* Restore the clobbered GR8 register
* (1st syscall arg was overwritten with syscall return or error)
*/
static inline void syscall_rollback(struct task_struct *task,
struct pt_regs *regs)
{
regs->gr8 = regs->orig_gr8;
}
/*
* See if the syscall return value is an error, returning it if it is and 0 if
* not
*/
static inline long syscall_get_error(struct task_struct *task,
struct pt_regs *regs)
{
return IS_ERR_VALUE(regs->gr8) ? regs->gr8 : 0;
}
/*
* Get the syscall return value
*/
static inline long syscall_get_return_value(struct task_struct *task,
struct pt_regs *regs)
{
return regs->gr8;
}
/*
* Set the syscall return value
*/
static inline void syscall_set_return_value(struct task_struct *task,
struct pt_regs *regs,
int error, long val)
{
if (error)
regs->gr8 = -error;
else
regs->gr8 = val;
}
/*
* Retrieve the system call arguments
*/
static inline void syscall_get_arguments(struct task_struct *task,
struct pt_regs *regs,
unsigned int i, unsigned int n,
unsigned long *args)
{
/*
* Do this simply for now. If we need to start supporting
* fetching arguments from arbitrary indices, this will need some
* extra logic. Presently there are no in-tree users that depend
* on this behaviour.
*/
BUG_ON(i);
/* Argument pattern is: GR8, GR9, GR10, GR11, GR12, GR13 */
switch (n) {
case 6: args[5] = regs->gr13;
case 5: args[4] = regs->gr12;
case 4: args[3] = regs->gr11;
case 3: args[2] = regs->gr10;
case 2: args[1] = regs->gr9;
case 1: args[0] = regs->gr8;
break;
default:
BUG();
}
}
/*
* Alter the system call arguments
*/
static inline void syscall_set_arguments(struct task_struct *task,
struct pt_regs *regs,
unsigned int i, unsigned int n,
const unsigned long *args)
{
/* Same note as above applies */
BUG_ON(i);
switch (n) {
case 6: regs->gr13 = args[5];
case 5: regs->gr12 = args[4];
case 4: regs->gr11 = args[3];
case 3: regs->gr10 = args[2];
case 2: regs->gr9 = args[1];
case 1: regs->gr8 = args[0];
break;
default:
BUG();
}
}
#endif /* _ASM_SYSCALL_H */
......@@ -1149,11 +1149,10 @@ __entry_work_notifysig:
# perform syscall entry tracing
__syscall_trace_entry:
LEDS 0x6320
setlos.p #0,gr8
call do_syscall_trace
call syscall_trace_entry
ldi @(gr28,#REG_SYSCALLNO),gr7
lddi @(gr28,#REG_GR(8)) ,gr8
lddi.p @(gr28,#REG_GR(8)) ,gr8
ori gr8,#0,gr7 ; syscall_trace_entry() returned new syscallno
lddi @(gr28,#REG_GR(10)),gr10
lddi.p @(gr28,#REG_GR(12)),gr12
......@@ -1168,11 +1167,10 @@ __syscall_exit_work:
beq icc0,#1,__entry_work_pending
movsg psr,gr23
andi gr23,#~PSR_PIL,gr23 ; could let do_syscall_trace() call schedule()
andi gr23,#~PSR_PIL,gr23 ; could let syscall_trace_exit() call schedule()
movgs gr23,psr
setlos.p #1,gr8
call do_syscall_trace
call syscall_trace_exit
bra __entry_resume_userspace
__syscall_badsys:
......
......@@ -19,6 +19,9 @@
#include <linux/user.h>
#include <linux/security.h>
#include <linux/signal.h>
#include <linux/regset.h>
#include <linux/elf.h>
#include <linux/tracehook.h>
#include <asm/uaccess.h>
#include <asm/page.h>
......@@ -32,6 +35,169 @@
* in exit.c or in signal.c.
*/
/*
* retrieve the contents of FRV userspace general registers
*/
static int genregs_get(struct task_struct *target,
const struct user_regset *regset,
unsigned int pos, unsigned int count,
void *kbuf, void __user *ubuf)
{
const struct user_int_regs *iregs = &target->thread.user->i;
int ret;
ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
iregs, 0, sizeof(*iregs));
if (ret < 0)
return ret;
return user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
sizeof(*iregs), -1);
}
/*
* update the contents of the FRV userspace general registers
*/
static int genregs_set(struct task_struct *target,
const struct user_regset *regset,
unsigned int pos, unsigned int count,
const void *kbuf, const void __user *ubuf)
{
struct user_int_regs *iregs = &target->thread.user->i;
unsigned int offs_gr0, offs_gr1;
int ret;
/* not allowed to set PSR or __status */
if (pos < offsetof(struct user_int_regs, psr) + sizeof(long) &&
pos + count > offsetof(struct user_int_regs, psr))
return -EIO;
if (pos < offsetof(struct user_int_regs, __status) + sizeof(long) &&
pos + count > offsetof(struct user_int_regs, __status))
return -EIO;
/* set the control regs */
offs_gr0 = offsetof(struct user_int_regs, gr[0]);
offs_gr1 = offsetof(struct user_int_regs, gr[1]);
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
iregs, 0, offs_gr0);
if (ret < 0)
return ret;
/* skip GR0/TBR */
ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
offs_gr0, offs_gr1);
if (ret < 0)
return ret;
/* set the general regs */
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
&iregs->gr[1], offs_gr1, sizeof(*iregs));
if (ret < 0)
return ret;
return user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
sizeof(*iregs), -1);
}
/*
* retrieve the contents of FRV userspace FP/Media registers
*/
static int fpmregs_get(struct task_struct *target,
const struct user_regset *regset,
unsigned int pos, unsigned int count,
void *kbuf, void __user *ubuf)
{
const struct user_fpmedia_regs *fpregs = &target->thread.user->f;
int ret;
ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
fpregs, 0, sizeof(*fpregs));
if (ret < 0)
return ret;
return user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
sizeof(*fpregs), -1);
}
/*
* update the contents of the FRV userspace FP/Media registers
*/
static int fpmregs_set(struct task_struct *target,
const struct user_regset *regset,
unsigned int pos, unsigned int count,
const void *kbuf, const void __user *ubuf)
{
struct user_fpmedia_regs *fpregs = &target->thread.user->f;
int ret;
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
fpregs, 0, sizeof(*fpregs));
if (ret < 0)
return ret;
return user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
sizeof(*fpregs), -1);
}
/*
* determine if the FP/Media registers have actually been used
*/
static int fpmregs_active(struct task_struct *target,
const struct user_regset *regset)
{
return tsk_used_math(target) ? regset->n : 0;
}
/*
* Define the register sets available on the FRV under Linux
*/
enum frv_regset {
REGSET_GENERAL,
REGSET_FPMEDIA,
};
static const struct user_regset frv_regsets[] = {
/*
* General register format is:
* PSR, ISR, CCR, CCCR, LR, LCR, PC, (STATUS), SYSCALLNO, ORIG_G8
* GNER0-1, IACC0, TBR, GR1-63
*/
[REGSET_GENERAL] = {
.core_note_type = NT_PRSTATUS,
.n = ELF_NGREG,
.size = sizeof(long),
.align = sizeof(long),
.get = genregs_get,
.set = genregs_set,
},
/*
* FPU/Media register format is:
* FR0-63, FNER0-1, MSR0-1, ACC0-7, ACCG0-8, FSR
*/
[REGSET_FPMEDIA] = {
.core_note_type = NT_PRFPREG,
.n = sizeof(struct user_fpmedia_regs) / sizeof(long),
.size = sizeof(long),
.align = sizeof(long),
.get = fpmregs_get,
.set = fpmregs_set,
.active = fpmregs_active,
},
};
static const struct user_regset_view user_frv_native_view = {
.name = "frv",
.e_machine = EM_FRV,
.regsets = frv_regsets,
.n = ARRAY_SIZE(frv_regsets),
};
const struct user_regset_view *task_user_regset_view(struct task_struct *task)
{
return &user_frv_native_view;
}
/*
* Get contents of register REGNO in task TASK.
*/
......@@ -68,41 +234,24 @@ static inline int put_reg(struct task_struct *task, int regno,
}
}
/*
* check that an address falls within the bounds of the target process's memory
* mappings
*/
static inline int is_user_addr_valid(struct task_struct *child,
unsigned long start, unsigned long len)
{
#ifdef CONFIG_MMU
if (start >= PAGE_OFFSET || len > PAGE_OFFSET - start)
return -EIO;
return 0;
#else
struct vm_area_struct *vma;
vma = find_vma(child->mm, start);
if (vma && start >= vma->vm_start && start + len <= vma->vm_end)
return 0;
return -EIO;
#endif
}
/*
* Called by kernel/ptrace.c when detaching..
*
* Control h/w single stepping
*/
void ptrace_disable(struct task_struct *child)
void user_enable_single_step(struct task_struct *child)
{
child->thread.frame0->__status |= REG__STATUS_STEP;
}
void user_disable_single_step(struct task_struct *child)
{
child->thread.frame0->__status &= ~REG__STATUS_STEP;
}
void ptrace_enable(struct task_struct *child)
void ptrace_disable(struct task_struct *child)
{
child->thread.frame0->__status |= REG__STATUS_STEP;
user_disable_single_step(child);
}
long arch_ptrace(struct task_struct *child, long request, long addr, long data)
......@@ -111,15 +260,6 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data)
int ret;
switch (request) {
/* when I and D space are separate, these will need to be fixed. */
case PTRACE_PEEKTEXT: /* read word at location addr. */
case PTRACE_PEEKDATA:
ret = -EIO;
if (is_user_addr_valid(child, addr, sizeof(tmp)) < 0)
break;
ret = generic_ptrace_peekdata(child, addr, data);
break;
/* read the word at location addr in the USER area. */
case PTRACE_PEEKUSR: {
tmp = 0;
......@@ -163,15 +303,6 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data)
break;
}
/* when I and D space are separate, this will have to be fixed. */
case PTRACE_POKETEXT: /* write the word at location addr. */
case PTRACE_POKEDATA:
ret = -EIO;
if (is_user_addr_valid(child, addr, sizeof(tmp)) < 0)
break;
ret = generic_ptrace_pokedata(child, addr, data);
break;
case PTRACE_POKEUSR: /* write the word at location addr in the USER area */
ret = -EIO;
if ((addr & 3) || addr < 0)
......@@ -179,7 +310,7 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data)
ret = 0;
switch (addr >> 2) {
case 0 ... PT__END-1:
case 0 ... PT__END - 1:
ret = put_reg(child, addr >> 2, data);
break;
......@@ -189,95 +320,29 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data)
}
break;
case PTRACE_SYSCALL: /* continue and stop at next (return from) syscall */
case PTRACE_CONT: /* restart after signal. */
ret = -EIO;
if (!valid_signal(data))
break;
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;
ptrace_disable(child);
wake_up_process(child);
ret = 0;
break;
/* 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:
ret = 0;
if (child->exit_state == EXIT_ZOMBIE) /* already dead */
break;
child->exit_code = SIGKILL;
clear_tsk_thread_flag(child, TIF_SINGLESTEP);
ptrace_disable(child);
wake_up_process(child);
break;
case PTRACE_SINGLESTEP: /* set the trap flag. */
ret = -EIO;
if (!valid_signal(data))
break;
clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
ptrace_enable(child);
child->exit_code = data;
wake_up_process(child);
ret = 0;
break;
case PTRACE_DETACH: /* detach a process that was attached. */
ret = ptrace_detach(child, data);
break;
case PTRACE_GETREGS: { /* Get all integer regs from the child. */
int i;
for (i = 0; i < PT__GPEND; i++) {
tmp = get_reg(child, i);
if (put_user(tmp, (unsigned long *) data)) {
ret = -EFAULT;
break;
}
data += sizeof(long);
}
ret = 0;
break;
}
case PTRACE_SETREGS: { /* Set all integer regs in the child. */
int i;
for (i = 0; i < PT__GPEND; i++) {
if (get_user(tmp, (unsigned long *) data)) {
ret = -EFAULT;
break;
}
put_reg(child, i, tmp);
data += sizeof(long);
}
ret = 0;
break;
}
case PTRACE_GETFPREGS: { /* Get the child FP/Media state. */
ret = 0;
if (copy_to_user((void *) data,
&child->thread.user->f,
sizeof(child->thread.user->f)))
ret = -EFAULT;
break;
}
case PTRACE_SETFPREGS: { /* Set the child FP/Media state. */
ret = 0;
if (copy_from_user(&child->thread.user->f,
(void *) data,
sizeof(child->thread.user->f)))
ret = -EFAULT;
break;
}
case PTRACE_GETREGS: /* Get all integer regs from the child. */
return copy_regset_to_user(child, &user_frv_native_view,
REGSET_GENERAL,
0, sizeof(child->thread.user->i),
(void __user *)data);
case PTRACE_SETREGS: /* Set all integer regs in the child. */
return copy_regset_from_user(child, &user_frv_native_view,
REGSET_GENERAL,
0, sizeof(child->thread.user->i),
(const void __user *)data);
case PTRACE_GETFPREGS: /* Get the child FP/Media state. */
return copy_regset_to_user(child, &user_frv_native_view,
REGSET_FPMEDIA,
0, sizeof(child->thread.user->f),
(void __user *)data);
case PTRACE_SETFPREGS: /* Set the child FP/Media state. */
return copy_regset_from_user(child, &user_frv_native_view,
REGSET_FPMEDIA,
0, sizeof(child->thread.user->f),
(const void __user *)data);
case PTRACE_GETFDPIC:
tmp = 0;
......@@ -300,35 +365,36 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data)
break;
default:
ret = -EIO;
ret = ptrace_request(child, request, addr, data);
break;
}
return ret;
}
asmlinkage void do_syscall_trace(int leaving)
/*
* handle tracing of system call entry
* - return the revised system call number or ULONG_MAX to cause ENOSYS
*/
asmlinkage unsigned long syscall_trace_entry(void)
{
if (!test_thread_flag(TIF_SYSCALL_TRACE))
return;
if (!(current->ptrace & PT_PTRACED))
return;
/* we need to indicate entry or exit to strace */
if (leaving)
__frame->__status |= REG__STATUS_SYSC_EXIT;
else
__frame->__status |= REG__STATUS_SYSC_ENTRY;
__frame->__status |= REG__STATUS_SYSC_ENTRY;
if (tracehook_report_syscall_entry(__frame)) {
/* tracing decided this syscall should not happen, so
* We'll return a bogus call number to get an ENOSYS
* error, but leave the original number in
* __frame->syscallno
*/