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linux/arch/m68k/kernel/signal.c

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/*
* linux/arch/m68k/kernel/signal.c
*
* Copyright (C) 1991, 1992 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.
*/
/*
* Linux/m68k support by Hamish Macdonald
*
* 68060 fixes by Jesper Skov
*
* 1997-12-01 Modified for POSIX.1b signals by Andreas Schwab
*
* mathemu support by Roman Zippel
* (Note: fpstate in the signal context is completely ignored for the emulator
* and the internal floating point format is put on stack)
*/
/*
* ++roman (07/09/96): implemented signal stacks (specially for tosemu on
* Atari :-) Current limitation: Only one sigstack can be active at one time.
* If a second signal with SA_ONSTACK set arrives while working on a sigstack,
* SA_ONSTACK is ignored. This behaviour avoids lots of trouble with nested
* signal handlers!
*/
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/kernel.h>
#include <linux/signal.h>
#include <linux/syscalls.h>
#include <linux/errno.h>
#include <linux/wait.h>
#include <linux/ptrace.h>
#include <linux/unistd.h>
#include <linux/stddef.h>
#include <linux/highuid.h>
#include <linux/personality.h>
#include <linux/tty.h>
#include <linux/binfmts.h>
#include <linux/extable.h>
#include <linux/tracehook.h>
#include <asm/setup.h>
#include <linux/uaccess.h>
#include <asm/pgtable.h>
#include <asm/traps.h>
#include <asm/ucontext.h>
#include <asm/cacheflush.h>
#ifdef CONFIG_MMU
/*
* Handle the slight differences in classic 68k and ColdFire trap frames.
*/
#ifdef CONFIG_COLDFIRE
#define FORMAT 4
#define FMT4SIZE 0
#else
#define FORMAT 0
#define FMT4SIZE sizeof(((struct frame *)0)->un.fmt4)
#endif
static const int frame_size_change[16] = {
[1] = -1, /* sizeof(((struct frame *)0)->un.fmt1), */
[2] = sizeof(((struct frame *)0)->un.fmt2),
[3] = sizeof(((struct frame *)0)->un.fmt3),
[4] = FMT4SIZE,
[5] = -1, /* sizeof(((struct frame *)0)->un.fmt5), */
[6] = -1, /* sizeof(((struct frame *)0)->un.fmt6), */
[7] = sizeof(((struct frame *)0)->un.fmt7),
[8] = -1, /* sizeof(((struct frame *)0)->un.fmt8), */
[9] = sizeof(((struct frame *)0)->un.fmt9),
[10] = sizeof(((struct frame *)0)->un.fmta),
[11] = sizeof(((struct frame *)0)->un.fmtb),
[12] = -1, /* sizeof(((struct frame *)0)->un.fmtc), */
[13] = -1, /* sizeof(((struct frame *)0)->un.fmtd), */
[14] = -1, /* sizeof(((struct frame *)0)->un.fmte), */
[15] = -1, /* sizeof(((struct frame *)0)->un.fmtf), */
};
static inline int frame_extra_sizes(int f)
{
return frame_size_change[f];
}
int fixup_exception(struct pt_regs *regs)
{
const struct exception_table_entry *fixup;
struct pt_regs *tregs;
/* Are we prepared to handle this kernel fault? */
fixup = search_exception_tables(regs->pc);
if (!fixup)
return 0;
/* Create a new four word stack frame, discarding the old one. */
regs->stkadj = frame_extra_sizes(regs->format);
tregs = (struct pt_regs *)((long)regs + regs->stkadj);
tregs->vector = regs->vector;
tregs->format = FORMAT;
tregs->pc = fixup->fixup;
tregs->sr = regs->sr;
return 1;
}
static inline void push_cache (unsigned long vaddr)
{
/*
* Using the old cache_push_v() was really a big waste.
*
* What we are trying to do is to flush 8 bytes to ram.
* Flushing 2 cache lines of 16 bytes is much cheaper than
* flushing 1 or 2 pages, as previously done in
* cache_push_v().
* Jes
*/
if (CPU_IS_040) {
unsigned long temp;
__asm__ __volatile__ (".chip 68040\n\t"
"nop\n\t"
"ptestr (%1)\n\t"
"movec %%mmusr,%0\n\t"
".chip 68k"
: "=r" (temp)
: "a" (vaddr));
temp &= PAGE_MASK;
temp |= vaddr & ~PAGE_MASK;
__asm__ __volatile__ (".chip 68040\n\t"
"nop\n\t"
"cpushl %%bc,(%0)\n\t"
".chip 68k"
: : "a" (temp));
}
else if (CPU_IS_060) {
unsigned long temp;
__asm__ __volatile__ (".chip 68060\n\t"
"plpar (%0)\n\t"
".chip 68k"
: "=a" (temp)
: "0" (vaddr));
__asm__ __volatile__ (".chip 68060\n\t"
"cpushl %%bc,(%0)\n\t"
".chip 68k"
: : "a" (temp));
} else if (!CPU_IS_COLDFIRE) {
/*
* 68030/68020 have no writeback cache;
* still need to clear icache.
* Note that vaddr is guaranteed to be long word aligned.
*/
unsigned long temp;
asm volatile ("movec %%cacr,%0" : "=r" (temp));
temp += 4;
asm volatile ("movec %0,%%caar\n\t"
"movec %1,%%cacr"
: : "r" (vaddr), "r" (temp));
asm volatile ("movec %0,%%caar\n\t"
"movec %1,%%cacr"
: : "r" (vaddr + 4), "r" (temp));
} else {
/* CPU_IS_COLDFIRE */
#if defined(CONFIG_CACHE_COPYBACK)
flush_cf_dcache(0, DCACHE_MAX_ADDR);
#endif
/* Invalidate instruction cache for the pushed bytes */
clear_cf_icache(vaddr, vaddr + 8);
}
}
static inline void adjustformat(struct pt_regs *regs)
{
}
static inline void save_a5_state(struct sigcontext *sc, struct pt_regs *regs)
{
}
#else /* CONFIG_MMU */
void ret_from_user_signal(void);
void ret_from_user_rt_signal(void);
static inline int frame_extra_sizes(int f)
{
/* No frame size adjustments required on non-MMU CPUs */
return 0;
}
static inline void adjustformat(struct pt_regs *regs)
{
/*
* set format byte to make stack appear modulo 4, which it will
* be when doing the rte
*/
regs->format = 0x4;
}
static inline void save_a5_state(struct sigcontext *sc, struct pt_regs *regs)
{
sc->sc_a5 = ((struct switch_stack *)regs - 1)->a5;
}
static inline void push_cache(unsigned long vaddr)
{
}
#endif /* CONFIG_MMU */
/*
* Do a signal return; undo the signal stack.
*
* Keep the return code on the stack quadword aligned!
* That makes the cache flush below easier.
*/
struct sigframe
{
char __user *pretcode;
int sig;
int code;
struct sigcontext __user *psc;
char retcode[8];
unsigned long extramask[_NSIG_WORDS-1];
struct sigcontext sc;
};
struct rt_sigframe
{
char __user *pretcode;
int sig;
struct siginfo __user *pinfo;
void __user *puc;
char retcode[8];
struct siginfo info;
struct ucontext uc;
};
#define FPCONTEXT_SIZE 216
#define uc_fpstate uc_filler[0]
#define uc_formatvec uc_filler[FPCONTEXT_SIZE/4]
#define uc_extra uc_filler[FPCONTEXT_SIZE/4+1]
#ifdef CONFIG_FPU
static unsigned char fpu_version; /* version number of fpu, set by setup_frame */
static inline int restore_fpu_state(struct sigcontext *sc)
{
int err = 1;
if (FPU_IS_EMU) {
/* restore registers */
memcpy(current->thread.fpcntl, sc->sc_fpcntl, 12);
memcpy(current->thread.fp, sc->sc_fpregs, 24);
return 0;
}
if (CPU_IS_060 ? sc->sc_fpstate[2] : sc->sc_fpstate[0]) {
/* Verify the frame format. */
if (!(CPU_IS_060 || CPU_IS_COLDFIRE) &&
(sc->sc_fpstate[0] != fpu_version))
goto out;
if (CPU_IS_020_OR_030) {
if (m68k_fputype & FPU_68881 &&
!(sc->sc_fpstate[1] == 0x18 || sc->sc_fpstate[1] == 0xb4))
goto out;
if (m68k_fputype & FPU_68882 &&
!(sc->sc_fpstate[1] == 0x38 || sc->sc_fpstate[1] == 0xd4))
goto out;
} else if (CPU_IS_040) {
if (!(sc->sc_fpstate[1] == 0x00 ||
sc->sc_fpstate[1] == 0x28 ||
sc->sc_fpstate[1] == 0x60))
goto out;
} else if (CPU_IS_060) {
if (!(sc->sc_fpstate[3] == 0x00 ||
sc->sc_fpstate[3] == 0x60 ||
sc->sc_fpstate[3] == 0xe0))
goto out;
} else if (CPU_IS_COLDFIRE) {
if (!(sc->sc_fpstate[0] == 0x00 ||
sc->sc_fpstate[0] == 0x05 ||
sc->sc_fpstate[0] == 0xe5))
goto out;
} else
goto out;
if (CPU_IS_COLDFIRE) {
__asm__ volatile ("fmovemd %0,%%fp0-%%fp1\n\t"
"fmovel %1,%%fpcr\n\t"
"fmovel %2,%%fpsr\n\t"
"fmovel %3,%%fpiar"
: /* no outputs */
: "m" (sc->sc_fpregs[0]),
"m" (sc->sc_fpcntl[0]),
"m" (sc->sc_fpcntl[1]),
"m" (sc->sc_fpcntl[2]));
} else {
__asm__ volatile (".chip 68k/68881\n\t"
"fmovemx %0,%%fp0-%%fp1\n\t"
"fmoveml %1,%%fpcr/%%fpsr/%%fpiar\n\t"
".chip 68k"
: /* no outputs */
: "m" (*sc->sc_fpregs),
"m" (*sc->sc_fpcntl));
}
}
if (CPU_IS_COLDFIRE) {
__asm__ volatile ("frestore %0" : : "m" (*sc->sc_fpstate));
} else {
__asm__ volatile (".chip 68k/68881\n\t"
"frestore %0\n\t"
".chip 68k"
: : "m" (*sc->sc_fpstate));
}
err = 0;
out:
return err;
}
static inline int rt_restore_fpu_state(struct ucontext __user *uc)
{
unsigned char fpstate[FPCONTEXT_SIZE];
int context_size = CPU_IS_060 ? 8 : (CPU_IS_COLDFIRE ? 12 : 0);
fpregset_t fpregs;
int err = 1;
if (FPU_IS_EMU) {
/* restore fpu control register */
if (__copy_from_user(current->thread.fpcntl,
uc->uc_mcontext.fpregs.f_fpcntl, 12))
goto out;
/* restore all other fpu register */
if (__copy_from_user(current->thread.fp,
uc->uc_mcontext.fpregs.f_fpregs, 96))
goto out;
return 0;
}
if (__get_user(*(long *)fpstate, (long __user *)&uc->uc_fpstate))
goto out;
if (CPU_IS_060 ? fpstate[2] : fpstate[0]) {
if (!(CPU_IS_060 || CPU_IS_COLDFIRE))
context_size = fpstate[1];
/* Verify the frame format. */
if (!(CPU_IS_060 || CPU_IS_COLDFIRE) &&
(fpstate[0] != fpu_version))
goto out;
if (CPU_IS_020_OR_030) {
if (m68k_fputype & FPU_68881 &&
!(context_size == 0x18 || context_size == 0xb4))
goto out;
if (m68k_fputype & FPU_68882 &&
!(context_size == 0x38 || context_size == 0xd4))
goto out;
} else if (CPU_IS_040) {
if (!(context_size == 0x00 ||
context_size == 0x28 ||
context_size == 0x60))
goto out;
} else if (CPU_IS_060) {
if (!(fpstate[3] == 0x00 ||
fpstate[3] == 0x60 ||
fpstate[3] == 0xe0))
goto out;
} else if (CPU_IS_COLDFIRE) {
if (!(fpstate[3] == 0x00 ||
fpstate[3] == 0x05 ||
fpstate[3] == 0xe5))
goto out;
} else
goto out;
if (__copy_from_user(&fpregs, &uc->uc_mcontext.fpregs,
sizeof(fpregs)))
goto out;
if (CPU_IS_COLDFIRE) {
__asm__ volatile ("fmovemd %0,%%fp0-%%fp7\n\t"
"fmovel %1,%%fpcr\n\t"
"fmovel %2,%%fpsr\n\t"
"fmovel %3,%%fpiar"
: /* no outputs */
: "m" (fpregs.f_fpregs[0]),
"m" (fpregs.f_fpcntl[0]),
"m" (fpregs.f_fpcntl[1]),
"m" (fpregs.f_fpcntl[2]));
} else {
__asm__ volatile (".chip 68k/68881\n\t"
"fmovemx %0,%%fp0-%%fp7\n\t"
"fmoveml %1,%%fpcr/%%fpsr/%%fpiar\n\t"
".chip 68k"
: /* no outputs */
: "m" (*fpregs.f_fpregs),
"m" (*fpregs.f_fpcntl));
}
}
if (context_size &&
__copy_from_user(fpstate + 4, (long __user *)&uc->uc_fpstate + 1,
context_size))
goto out;
if (CPU_IS_COLDFIRE) {
__asm__ volatile ("frestore %0" : : "m" (*fpstate));
} else {
__asm__ volatile (".chip 68k/68881\n\t"
"frestore %0\n\t"
".chip 68k"
: : "m" (*fpstate));
}
err = 0;
out:
return err;
}
/*
* Set up a signal frame.
*/
static inline void save_fpu_state(struct sigcontext *sc, struct pt_regs *regs)
{
if (FPU_IS_EMU) {
/* save registers */
memcpy(sc->sc_fpcntl, current->thread.fpcntl, 12);
memcpy(sc->sc_fpregs, current->thread.fp, 24);
return;
}
if (CPU_IS_COLDFIRE) {
__asm__ volatile ("fsave %0"
: : "m" (*sc->sc_fpstate) : "memory");
} else {
__asm__ volatile (".chip 68k/68881\n\t"
"fsave %0\n\t"
".chip 68k"
: : "m" (*sc->sc_fpstate) : "memory");
}
if (CPU_IS_060 ? sc->sc_fpstate[2] : sc->sc_fpstate[0]) {
fpu_version = sc->sc_fpstate[0];
if (CPU_IS_020_OR_030 &&
regs->vector >= (VEC_FPBRUC * 4) &&
regs->vector <= (VEC_FPNAN * 4)) {
/* Clear pending exception in 68882 idle frame */
if (*(unsigned short *) sc->sc_fpstate == 0x1f38)
sc->sc_fpstate[0x38] |= 1 << 3;
}
if (CPU_IS_COLDFIRE) {
__asm__ volatile ("fmovemd %%fp0-%%fp1,%0\n\t"
"fmovel %%fpcr,%1\n\t"
"fmovel %%fpsr,%2\n\t"
"fmovel %%fpiar,%3"
: "=m" (sc->sc_fpregs[0]),
"=m" (sc->sc_fpcntl[0]),
"=m" (sc->sc_fpcntl[1]),
"=m" (sc->sc_fpcntl[2])
: /* no inputs */
: "memory");
} else {
__asm__ volatile (".chip 68k/68881\n\t"
"fmovemx %%fp0-%%fp1,%0\n\t"
"fmoveml %%fpcr/%%fpsr/%%fpiar,%1\n\t"
".chip 68k"
: "=m" (*sc->sc_fpregs),
"=m" (*sc->sc_fpcntl)
: /* no inputs */
: "memory");
}
}
}
static inline int rt_save_fpu_state(struct ucontext __user *uc, struct pt_regs *regs)
{
unsigned char fpstate[FPCONTEXT_SIZE];
int context_size = CPU_IS_060 ? 8 : (CPU_IS_COLDFIRE ? 12 : 0);
int err = 0;
if (FPU_IS_EMU) {
/* save fpu control register */
err |= copy_to_user(uc->uc_mcontext.fpregs.f_fpcntl,
current->thread.fpcntl, 12);
/* save all other fpu register */
err |= copy_to_user(uc->uc_mcontext.fpregs.f_fpregs,
current->thread.fp, 96);
return err;
}
if (CPU_IS_COLDFIRE) {
__asm__ volatile ("fsave %0" : : "m" (*fpstate) : "memory");
} else {
__asm__ volatile (".chip 68k/68881\n\t"
"fsave %0\n\t"
".chip 68k"
: : "m" (*fpstate) : "memory");
}
err |= __put_user(*(long *)fpstate, (long __user *)&uc->uc_fpstate);
if (CPU_IS_060 ? fpstate[2] : fpstate[0]) {
fpregset_t fpregs;
if (!(CPU_IS_060 || CPU_IS_COLDFIRE))
context_size = fpstate[1];
fpu_version = fpstate[0];
if (CPU_IS_020_OR_030 &&
regs->vector >= (VEC_FPBRUC * 4) &&
regs->vector <= (VEC_FPNAN * 4)) {
/* Clear pending exception in 68882 idle frame */
if (*(unsigned short *) fpstate == 0x1f38)
fpstate[0x38] |= 1 << 3;
}
if (CPU_IS_COLDFIRE) {
__asm__ volatile ("fmovemd %%fp0-%%fp7,%0\n\t"
"fmovel %%fpcr,%1\n\t"
"fmovel %%fpsr,%2\n\t"
"fmovel %%fpiar,%3"
: "=m" (fpregs.f_fpregs[0]),
"=m" (fpregs.f_fpcntl[0]),
"=m" (fpregs.f_fpcntl[1]),
"=m" (fpregs.f_fpcntl[2])
: /* no inputs */
: "memory");
} else {
__asm__ volatile (".chip 68k/68881\n\t"
"fmovemx %%fp0-%%fp7,%0\n\t"
"fmoveml %%fpcr/%%fpsr/%%fpiar,%1\n\t"
".chip 68k"
: "=m" (*fpregs.f_fpregs),
"=m" (*fpregs.f_fpcntl)
: /* no inputs */
: "memory");
}
err |= copy_to_user(&uc->uc_mcontext.fpregs, &fpregs,
sizeof(fpregs));
}
if (context_size)
err |= copy_to_user((long __user *)&uc->uc_fpstate + 1, fpstate + 4,
context_size);
return err;
}
#else /* CONFIG_FPU */
/*
* For the case with no FPU configured these all do nothing.
*/
static inline int restore_fpu_state(struct sigcontext *sc)
{
return 0;
}
static inline int rt_restore_fpu_state(struct ucontext __user *uc)
{
return 0;
}
static inline void save_fpu_state(struct sigcontext *sc, struct pt_regs *regs)
{
}
static inline int rt_save_fpu_state(struct ucontext __user *uc, struct pt_regs *regs)
{
return 0;
}
#endif /* CONFIG_FPU */
static int mangle_kernel_stack(struct pt_regs *regs, int formatvec,
void __user *fp)
{
int fsize = frame_extra_sizes(formatvec >> 12);
if (fsize < 0) {
/*
* user process trying to return with weird frame format
*/
pr_debug("user process returning with weird frame format\n");
return 1;
}
if (!fsize) {
regs->format = formatvec >> 12;
regs->vector = formatvec & 0xfff;
} else {
struct switch_stack *sw = (struct switch_stack *)regs - 1;
unsigned long buf[fsize / 2]; /* yes, twice as much */
/* that'll make sure that expansion won't crap over data */
if (copy_from_user(buf + fsize / 4, fp, fsize))
return 1;
/* point of no return */
regs->format = formatvec >> 12;
regs->vector = formatvec & 0xfff;
#define frame_offset (sizeof(struct pt_regs)+sizeof(struct switch_stack))
__asm__ __volatile__ (
#ifdef CONFIG_COLDFIRE
" movel %0,%/sp\n\t"
" bra ret_from_signal\n"
#else
" movel %0,%/a0\n\t"
" subl %1,%/a0\n\t" /* make room on stack */
" movel %/a0,%/sp\n\t" /* set stack pointer */
/* move switch_stack and pt_regs */
"1: movel %0@+,%/a0@+\n\t"
" dbra %2,1b\n\t"
" lea %/sp@(%c3),%/a0\n\t" /* add offset of fmt */
" lsrl #2,%1\n\t"
" subql #1,%1\n\t"
/* copy to the gap we'd made */
"2: movel %4@+,%/a0@+\n\t"
" dbra %1,2b\n\t"
" bral ret_from_signal\n"
#endif
: /* no outputs, it doesn't ever return */
: "a" (sw), "d" (fsize), "d" (frame_offset/4-1),
"n" (frame_offset), "a" (buf + fsize/4)
: "a0");
#undef frame_offset
}
return 0;
}
static inline int
restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *usc, void __user *fp)
{
int formatvec;
struct sigcontext context;
int err = 0;
/* Always make any pending restarted system calls return -EINTR */
current->restart_block.fn = do_no_restart_syscall;
/* get previous context */
if (copy_from_user(&context, usc, sizeof(context)))
goto badframe;
/* restore passed registers */
regs->d0 = context.sc_d0;
regs->d1 = context.sc_d1;
regs->a0 = context.sc_a0;
regs->a1 = context.sc_a1;
regs->sr = (regs->sr & 0xff00) | (context.sc_sr & 0xff);
regs->pc = context.sc_pc;
regs->orig_d0 = -1; /* disable syscall checks */
wrusp(context.sc_usp);
formatvec = context.sc_formatvec;
err = restore_fpu_state(&context);
if (err || mangle_kernel_stack(regs, formatvec, fp))
goto badframe;
return 0;
badframe:
return 1;
}
static inline int
rt_restore_ucontext(struct pt_regs *regs, struct switch_stack *sw,
struct ucontext __user *uc)
{
int temp;
greg_t __user *gregs = uc->uc_mcontext.gregs;
unsigned long usp;
int err;
/* Always make any pending restarted system calls return -EINTR */
current->restart_block.fn = do_no_restart_syscall;
err = __get_user(temp, &uc->uc_mcontext.version);
if (temp != MCONTEXT_VERSION)
goto badframe;
/* restore passed registers */
err |= __get_user(regs->d0, &gregs[0]);
err |= __get_user(regs->d1, &gregs[1]);
err |= __get_user(regs->d2, &gregs[2]);
err |= __get_user(regs->d3, &gregs[3]);
err |= __get_user(regs->d4, &gregs[4]);
err |= __get_user(regs->d5, &gregs[5]);
err |= __get_user(sw->d6, &gregs[6]);
err |= __get_user(sw->d7, &gregs[7]);
err |= __get_user(regs->a0, &gregs[8]);
err |= __get_user(regs->a1, &gregs[9]);
err |= __get_user(regs->a2, &gregs[10]);
err |= __get_user(sw->a3, &gregs[11]);
err |= __get_user(sw->a4, &gregs[12]);
err |= __get_user(sw->a5, &gregs[13]);
err |= __get_user(sw->a6, &gregs[14]);
err |= __get_user(usp, &gregs[15]);
wrusp(usp);
err |= __get_user(regs->pc, &gregs[16]);
err |= __get_user(temp, &gregs[17]);
regs->sr = (regs->sr & 0xff00) | (temp & 0xff);
regs->orig_d0 = -1; /* disable syscall checks */
err |= __get_user(temp, &uc->uc_formatvec);
err |= rt_restore_fpu_state(uc);
err |= restore_altstack(&uc->uc_stack);
if (err)
goto badframe;
if (mangle_kernel_stack(regs, temp, &uc->uc_extra))
goto badframe;
return 0;
badframe:
return 1;
}
asmlinkage int do_sigreturn(struct pt_regs *regs, struct switch_stack *sw)
{
unsigned long usp = rdusp();
struct sigframe __user *frame = (struct sigframe __user *)(usp - 4);
sigset_t set;
if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
goto badframe;
if (__get_user(set.sig[0], &frame->sc.sc_mask) ||
(_NSIG_WORDS > 1 &&
__copy_from_user(&set.sig[1], &frame->extramask,
sizeof(frame->extramask))))
goto badframe;
set_current_blocked(&set);
if (restore_sigcontext(regs, &frame->sc, frame + 1))
goto badframe;
return regs->d0;
badframe:
force_sig(SIGSEGV, current);
return 0;
}
asmlinkage int do_rt_sigreturn(struct pt_regs *regs, struct switch_stack *sw)
{
unsigned long usp = rdusp();
struct rt_sigframe __user *frame = (struct rt_sigframe __user *)(usp - 4);
sigset_t set;
if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
goto badframe;
if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
goto badframe;
set_current_blocked(&set);
if (rt_restore_ucontext(regs, sw, &frame->uc))
goto badframe;
return regs->d0;
badframe:
force_sig(SIGSEGV, current);
return 0;
}
static void setup_sigcontext(struct sigcontext *sc, struct pt_regs *regs,
unsigned long mask)
{
sc->sc_mask = mask;
sc->sc_usp = rdusp();
sc->sc_d0 = regs->d0;
sc->sc_d1 = regs->d1;
sc->sc_a0 = regs->a0;
sc->sc_a1 = regs->a1;
sc->sc_sr = regs->sr;
sc->sc_pc = regs->pc;
sc->sc_formatvec = regs->format << 12 | regs->vector;
save_a5_state(sc, regs);
save_fpu_state(sc, regs);
}
static inline int rt_setup_ucontext(struct ucontext __user *uc, struct pt_regs *regs)
{
struct switch_stack *sw = (struct switch_stack *)regs - 1;
greg_t __user *gregs = uc->uc_mcontext.gregs;
int err = 0;
err |= __put_user(MCONTEXT_VERSION, &uc->uc_mcontext.version);
err |= __put_user(regs->d0, &gregs[0]);
err |= __put_user(regs->d1, &gregs[1]);
err |= __put_user(regs->d2, &gregs[2]);
err |= __put_user(regs->d3, &gregs[3]);
err |= __put_user(regs->d4, &gregs[4]);
err |= __put_user(regs->d5, &gregs[5]);
err |= __put_user(sw->d6, &gregs[6]);
err |= __put_user(sw->d7, &gregs[7]);
err |= __put_user(regs->a0, &gregs[8]);
err |= __put_user(regs->a1, &gregs[9]);
err |= __put_user(regs->a2, &gregs[10]);
err |= __put_user(sw->a3, &gregs[11]);
err |= __put_user(sw->a4, &gregs[12]);
err |= __put_user(sw->a5, &gregs[13]);
err |= __put_user(sw->a6, &gregs[14]);
err |= __put_user(rdusp(), &gregs[15]);
err |= __put_user(regs->pc, &gregs[16]);
err |= __put_user(regs->sr, &gregs[17]);
err |= __put_user((regs->format << 12) | regs->vector, &uc->uc_formatvec);
err |= rt_save_fpu_state(uc, regs);
return err;
}
static inline void __user *
get_sigframe(struct ksignal *ksig, size_t frame_size)
{
unsigned long usp = sigsp(rdusp(), ksig);
return (void __user *)((usp - frame_size) & -8UL);
}
static int setup_frame(struct ksignal *ksig, sigset_t *set,
struct pt_regs *regs)
{
struct sigframe __user *frame;
int fsize = frame_extra_sizes(regs->format);
struct sigcontext context;
int err = 0, sig = ksig->sig;
if (fsize < 0) {
pr_debug("setup_frame: Unknown frame format %#x\n",
regs->format);
return -EFAULT;
}
frame = get_sigframe(ksig, sizeof(*frame) + fsize);
if (fsize)
err |= copy_to_user (frame + 1, regs + 1, fsize);
err |= __put_user(sig, &frame->sig);
err |= __put_user(regs->vector, &frame->code);
err |= __put_user(&frame->sc, &frame->psc);
if (_NSIG_WORDS > 1)
err |= copy_to_user(frame->extramask, &set->sig[1],
sizeof(frame->extramask));
setup_sigcontext(&context, regs, set->sig[0]);
err |= copy_to_user (&frame->sc, &context, sizeof(context));
/* Set up to return from userspace. */
#ifdef CONFIG_MMU
err |= __put_user(frame->retcode, &frame->pretcode);
/* moveq #,d0; trap #0 */
err |= __put_user(0x70004e40 + (__NR_sigreturn << 16),
(long __user *)(frame->retcode));
#else
err |= __put_user((void *) ret_from_user_signal, &frame->pretcode);
#endif
if (err)
return -EFAULT;
push_cache ((unsigned long) &frame->retcode);
/*
* Set up registers for signal handler. All the state we are about
* to destroy is successfully copied to sigframe.
*/
wrusp ((unsigned long) frame);
regs->pc = (unsigned long) ksig->ka.sa.sa_handler;
adjustformat(regs);
/*
* This is subtle; if we build more than one sigframe, all but the
* first one will see frame format 0 and have fsize == 0, so we won't
* screw stkadj.
*/
if (fsize)
regs->stkadj = fsize;
/* Prepare to skip over the extra stuff in the exception frame. */
if (regs->stkadj) {
struct pt_regs *tregs =
(struct pt_regs *)((ulong)regs + regs->stkadj);
pr_debug("Performing stackadjust=%04lx\n", regs->stkadj);
/* This must be copied with decreasing addresses to
handle overlaps. */
tregs->vector = 0;
tregs->format = 0;
tregs->pc = regs->pc;
tregs->sr = regs->sr;
}
return 0;
}
static int setup_rt_frame(struct ksignal *ksig, sigset_t *set,
struct pt_regs *regs)
{
struct rt_sigframe __user *frame;
int fsize = frame_extra_sizes(regs->format);
int err = 0, sig = ksig->sig;
if (fsize < 0) {
pr_debug("setup_frame: Unknown frame format %#x\n",
regs->format);
return -EFAULT;
}
frame = get_sigframe(ksig, sizeof(*frame));
if (fsize)
err |= copy_to_user (&frame->uc.uc_extra, regs + 1, fsize);
err |= __put_user(sig, &frame->sig);
err |= __put_user(&frame->info, &frame->pinfo);
err |= __put_user(&frame->uc, &frame->puc);
err |= copy_siginfo_to_user(&frame->info, &ksig->info);
/* Create the ucontext. */
err |= __put_user(0, &frame->uc.uc_flags);
err |= __put_user(NULL, &frame->uc.uc_link);
err |= __save_altstack(&frame->uc.uc_stack, rdusp());
err |= rt_setup_ucontext(&frame->uc, regs);
err |= copy_to_user (&frame->uc.uc_sigmask, set, sizeof(*set));
/* Set up to return from userspace. */
#ifdef CONFIG_MMU
err |= __put_user(frame->retcode, &frame->pretcode);
#ifdef __mcoldfire__
/* movel #__NR_rt_sigreturn,d0; trap #0 */
err |= __put_user(0x203c0000, (long __user *)(frame->retcode + 0));
err |= __put_user(0x00004e40 + (__NR_rt_sigreturn << 16),
(long __user *)(frame->retcode + 4));
#else
/* moveq #,d0; notb d0; trap #0 */
err |= __put_user(0x70004600 + ((__NR_rt_sigreturn ^ 0xff) << 16),
(long __user *)(frame->retcode + 0));
err |= __put_user(0x4e40, (short __user *)(frame->retcode + 4));
#endif
#else
err |= __put_user((void *) ret_from_user_rt_signal, &frame->pretcode);
#endif /* CONFIG_MMU */
if (err)
return -EFAULT;
push_cache ((unsigned long) &frame->retcode);
/*
* Set up registers for signal handler. All the state we are about
* to destroy is successfully copied to sigframe.
*/
wrusp ((unsigned long) frame);
regs->pc = (unsigned long) ksig->ka.sa.sa_handler;
adjustformat(regs);
/*
* This is subtle; if we build more than one sigframe, all but the
* first one will see frame format 0 and have fsize == 0, so we won't
* screw stkadj.
*/
if (fsize)
regs->stkadj = fsize;
/* Prepare to skip over the extra stuff in the exception frame. */
if (regs->stkadj) {
struct pt_regs *tregs =
(struct pt_regs *)((ulong)regs + regs->stkadj);
pr_debug("Performing stackadjust=%04lx\n", regs->stkadj);
/* This must be copied with decreasing addresses to
handle overlaps. */
tregs->vector = 0;
tregs->format = 0;
tregs->pc = regs->pc;
tregs->sr = regs->sr;
}
return 0;
}
static inline void
handle_restart(struct pt_regs *regs, struct k_sigaction *ka, int has_handler)
{
switch (regs->d0) {
case -ERESTARTNOHAND:
if (!has_handler)
goto do_restart;
regs->d0 = -EINTR;
break;
case -ERESTART_RESTARTBLOCK:
if (!has_handler) {
regs->d0 = __NR_restart_syscall;
regs->pc -= 2;
break;
}
regs->d0 = -EINTR;
break;
case -ERESTARTSYS:
if (has_handler && !(ka->sa.sa_flags & SA_RESTART)) {
regs->d0 = -EINTR;
break;
}
/* fallthrough */
case -ERESTARTNOINTR:
do_restart:
regs->d0 = regs->orig_d0;
regs->pc -= 2;
break;
}
}
/*
* OK, we're invoking a handler
*/
static void
handle_signal(struct ksignal *ksig, struct pt_regs *regs)
{
sigset_t *oldset = sigmask_to_save();
int err;
/* are we from a system call? */
if (regs->orig_d0 >= 0)
/* If so, check system call restarting.. */
handle_restart(regs, &ksig->ka, 1);
/* set up the stack frame */
if (ksig->ka.sa.sa_flags & SA_SIGINFO)
err = setup_rt_frame(ksig, oldset, regs);
else
err = setup_frame(ksig, oldset, regs);
signal_setup_done(err, ksig, 0);
if (test_thread_flag(TIF_DELAYED_TRACE)) {
regs->sr &= ~0x8000;
send_sig(SIGTRAP, current, 1);
}
}
/*
* Note that 'init' is a special process: it doesn't get signals it doesn't
* want to handle. Thus you cannot kill init even with a SIGKILL even by
* mistake.
*/
static void do_signal(struct pt_regs *regs)
{
struct ksignal ksig;
current->thread.esp0 = (unsigned long) regs;
if (get_signal(&ksig)) {
/* Whee! Actually deliver the signal. */
handle_signal(&ksig, regs);
return;
}
/* Did we come from a system call? */
if (regs->orig_d0 >= 0)
/* Restart the system call - no handlers present */
handle_restart(regs, NULL, 0);
/* If there's no signal to deliver, we just restore the saved mask. */
restore_saved_sigmask();
}
void do_notify_resume(struct pt_regs *regs)
{
if (test_thread_flag(TIF_SIGPENDING))
do_signal(regs);
if (test_and_clear_thread_flag(TIF_NOTIFY_RESUME))
tracehook_notify_resume(regs);
}
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