redonkable/alistair23-linux
redonkable/alistair23-linux
1
0
Fork 0
Code Releases Activity
alistair23-linux/arch/sh/kernel/traps_32.c
Paul Gortmaker 4603f53a1d sh: delete __cpuinit usage from all sh files 
The __cpuinit type of throwaway sections might have made sense
some time ago when RAM was more constrained, but now the savings
do not offset the cost and complications.  For example, the fix in
commit 5e427ec2d0 ("x86: Fix bit corruption at CPU resume time")
is a good example of the nasty type of bugs that can be created
with improper use of the various __init prefixes.

After a discussion on LKML[1] it was decided that cpuinit should go
the way of devinit and be phased out.  Once all the users are gone,
we can then finally remove the macros themselves from linux/init.h.

Note that some harmless section mismatch warnings may result, since
notify_cpu_starting() and cpu_up() are arch independent (kernel/cpu.c)
are flagged as __cpuinit  -- so if we remove the __cpuinit from
arch specific callers, we will also get section mismatch warnings.
As an intermediate step, we intend to turn the linux/init.h cpuinit
content into no-ops as early as possible, since that will get rid
of these warnings.  In any case, they are temporary and harmless.

This removes all the arch/sh uses of the __cpuinit macros from
all C files.  Currently sh does not have any __CPUINIT used in
assembly files.

[1] https://lkml.org/lkml/2013/5/20/589

Cc: Paul Mundt <lethal@linux-sh.org>
Cc: linux-sh@vger.kernel.org
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2013-07-14 19:36:53 -04:00

805 lines
19 KiB
C
Raw Blame History

/*
* 'traps.c' handles hardware traps and faults after we have saved some
* state in 'entry.S'.
*
* SuperH version: Copyright (C) 1999 Niibe Yutaka
* Copyright (C) 2000 Philipp Rumpf
* Copyright (C) 2000 David Howells
* Copyright (C) 2002 - 2010 Paul Mundt
*
* 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/kernel.h>
#include <linux/ptrace.h>
#include <linux/hardirq.h>
#include <linux/init.h>
#include <linux/spinlock.h>
#include <linux/kallsyms.h>
#include <linux/io.h>
#include <linux/bug.h>
#include <linux/debug_locks.h>
#include <linux/kdebug.h>
#include <linux/limits.h>
#include <linux/sysfs.h>
#include <linux/uaccess.h>
#include <linux/perf_event.h>
#include <asm/alignment.h>
#include <asm/fpu.h>
#include <asm/kprobes.h>
#include <asm/traps.h>
#include <asm/bl_bit.h>
#ifdef CONFIG_CPU_SH2
# define TRAP_RESERVED_INST 4
# define TRAP_ILLEGAL_SLOT_INST 6
# define TRAP_ADDRESS_ERROR 9
# ifdef CONFIG_CPU_SH2A
# define TRAP_UBC 12
# define TRAP_FPU_ERROR 13
# define TRAP_DIVZERO_ERROR 17
# define TRAP_DIVOVF_ERROR 18
# endif
#else
#define TRAP_RESERVED_INST 12
#define TRAP_ILLEGAL_SLOT_INST 13
#endif
static inline void sign_extend(unsigned int count, unsigned char *dst)
{
#ifdef __LITTLE_ENDIAN__
if ((count == 1) && dst[0] & 0x80) {
dst[1] = 0xff;
dst[2] = 0xff;
dst[3] = 0xff;
}
if ((count == 2) && dst[1] & 0x80) {
dst[2] = 0xff;
dst[3] = 0xff;
}
#else
if ((count == 1) && dst[3] & 0x80) {
dst[2] = 0xff;
dst[1] = 0xff;
dst[0] = 0xff;
}
if ((count == 2) && dst[2] & 0x80) {
dst[1] = 0xff;
dst[0] = 0xff;
}
#endif
}
static struct mem_access user_mem_access = {
copy_from_user,
copy_to_user,
};
/*
* handle an instruction that does an unaligned memory access by emulating the
* desired behaviour
* - note that PC _may not_ point to the faulting instruction
* (if that instruction is in a branch delay slot)
* - return 0 if emulation okay, -EFAULT on existential error
*/
static int handle_unaligned_ins(insn_size_t instruction, struct pt_regs *regs,
struct mem_access *ma)
{
int ret, index, count;
unsigned long *rm, *rn;
unsigned char *src, *dst;
unsigned char __user *srcu, *dstu;
index = (instruction>>8)&15; /* 0x0F00 */
rn = &regs->regs[index];
index = (instruction>>4)&15; /* 0x00F0 */
rm = &regs->regs[index];
count = 1<<(instruction&3);
switch (count) {
case 1: inc_unaligned_byte_access(); break;
case 2: inc_unaligned_word_access(); break;
case 4: inc_unaligned_dword_access(); break;
case 8: inc_unaligned_multi_access(); break;
}
ret = -EFAULT;
switch (instruction>>12) {
case 0: /* mov.[bwl] to/from memory via r0+rn */
if (instruction & 8) {
/* from memory */
srcu = (unsigned char __user *)*rm;
srcu += regs->regs[0];
dst = (unsigned char *)rn;
*(unsigned long *)dst = 0;
#if !defined(__LITTLE_ENDIAN__)
dst += 4-count;
#endif
if (ma->from(dst, srcu, count))
goto fetch_fault;
sign_extend(count, dst);
} else {
/* to memory */
src = (unsigned char *)rm;
#if !defined(__LITTLE_ENDIAN__)
src += 4-count;
#endif
dstu = (unsigned char __user *)*rn;
dstu += regs->regs[0];
if (ma->to(dstu, src, count))
goto fetch_fault;
}
ret = 0;
break;
case 1: /* mov.l Rm,@(disp,Rn) */
src = (unsigned char*) rm;
dstu = (unsigned char __user *)*rn;
dstu += (instruction&0x000F)<<2;
if (ma->to(dstu, src, 4))
goto fetch_fault;
ret = 0;
break;
case 2: /* mov.[bwl] to memory, possibly with pre-decrement */
if (instruction & 4)
*rn -= count;
src = (unsigned char*) rm;
dstu = (unsigned char __user *)*rn;
#if !defined(__LITTLE_ENDIAN__)
src += 4-count;
#endif
if (ma->to(dstu, src, count))
goto fetch_fault;
ret = 0;
break;
case 5: /* mov.l @(disp,Rm),Rn */
srcu = (unsigned char __user *)*rm;
srcu += (instruction & 0x000F) << 2;
dst = (unsigned char *)rn;
*(unsigned long *)dst = 0;
if (ma->from(dst, srcu, 4))
goto fetch_fault;
ret = 0;
break;
case 6: /* mov.[bwl] from memory, possibly with post-increment */
srcu = (unsigned char __user *)*rm;
if (instruction & 4)
*rm += count;
dst = (unsigned char*) rn;
*(unsigned long*)dst = 0;
#if !defined(__LITTLE_ENDIAN__)
dst += 4-count;
#endif
if (ma->from(dst, srcu, count))
goto fetch_fault;
sign_extend(count, dst);
ret = 0;
break;
case 8:
switch ((instruction&0xFF00)>>8) {
case 0x81: /* mov.w R0,@(disp,Rn) */
src = (unsigned char *) &regs->regs[0];
#if !defined(__LITTLE_ENDIAN__)
src += 2;
#endif
dstu = (unsigned char __user *)*rm; /* called Rn in the spec */
dstu += (instruction & 0x000F) << 1;
if (ma->to(dstu, src, 2))
goto fetch_fault;
ret = 0;
break;
case 0x85: /* mov.w @(disp,Rm),R0 */
srcu = (unsigned char __user *)*rm;
srcu += (instruction & 0x000F) << 1;
dst = (unsigned char *) &regs->regs[0];
*(unsigned long *)dst = 0;
#if !defined(__LITTLE_ENDIAN__)
dst += 2;
#endif
if (ma->from(dst, srcu, 2))
goto fetch_fault;
sign_extend(2, dst);
ret = 0;
break;
}
break;
case 9: /* mov.w @(disp,PC),Rn */
srcu = (unsigned char __user *)regs->pc;
srcu += 4;
srcu += (instruction & 0x00FF) << 1;
dst = (unsigned char *)rn;
*(unsigned long *)dst = 0;
#if !defined(__LITTLE_ENDIAN__)
dst += 2;
#endif
if (ma->from(dst, srcu, 2))
goto fetch_fault;
sign_extend(2, dst);
ret = 0;
break;
case 0xd: /* mov.l @(disp,PC),Rn */
srcu = (unsigned char __user *)(regs->pc & ~0x3);
srcu += 4;
srcu += (instruction & 0x00FF) << 2;
dst = (unsigned char *)rn;
*(unsigned long *)dst = 0;
if (ma->from(dst, srcu, 4))
goto fetch_fault;
ret = 0;
break;
}
return ret;
fetch_fault:
/* Argh. Address not only misaligned but also non-existent.
* Raise an EFAULT and see if it's trapped
*/
die_if_no_fixup("Fault in unaligned fixup", regs, 0);
return -EFAULT;
}
/*
* emulate the instruction in the delay slot
* - fetches the instruction from PC+2
*/
static inline int handle_delayslot(struct pt_regs *regs,
insn_size_t old_instruction,
struct mem_access *ma)
{
insn_size_t instruction;
void __user *addr = (void __user *)(regs->pc +
instruction_size(old_instruction));
if (copy_from_user(&instruction, addr, sizeof(instruction))) {
/* the instruction-fetch faulted */
if (user_mode(regs))
return -EFAULT;
/* kernel */
die("delay-slot-insn faulting in handle_unaligned_delayslot",
regs, 0);
}
return handle_unaligned_ins(instruction, regs, ma);
}
/*
* handle an instruction that does an unaligned memory access
* - have to be careful of branch delay-slot instructions that fault
* SH3:
* - if the branch would be taken PC points to the branch
* - if the branch would not be taken, PC points to delay-slot
* SH4:
* - PC always points to delayed branch
* - return 0 if handled, -EFAULT if failed (may not return if in kernel)
*/
/* Macros to determine offset from current PC for branch instructions */
/* Explicit type coercion is used to force sign extension where needed */
#define SH_PC_8BIT_OFFSET(instr) ((((signed char)(instr))*2) + 4)
#define SH_PC_12BIT_OFFSET(instr) ((((signed short)(instr<<4))>>3) + 4)
int handle_unaligned_access(insn_size_t instruction, struct pt_regs *regs,
struct mem_access *ma, int expected,
unsigned long address)
{
u_int rm;
int ret, index;
/*
* XXX: We can't handle mixed 16/32-bit instructions yet
*/
if (instruction_size(instruction) != 2)
return -EINVAL;
index = (instruction>>8)&15; /* 0x0F00 */
rm = regs->regs[index];
/*
* Log the unexpected fixups, and then pass them on to perf.
*
* We intentionally don't report the expected cases to perf as
* otherwise the trapped I/O case will skew the results too much
* to be useful.
*/
if (!expected) {
unaligned_fixups_notify(current, instruction, regs);
perf_sw_event(PERF_COUNT_SW_ALIGNMENT_FAULTS, 1,
regs, address);
}
ret = -EFAULT;
switch (instruction&0xF000) {
case 0x0000:
if (instruction==0x000B) {
/* rts */
ret = handle_delayslot(regs, instruction, ma);
if (ret==0)
regs->pc = regs->pr;
}
else if ((instruction&0x00FF)==0x0023) {
/* braf @Rm */
ret = handle_delayslot(regs, instruction, ma);
if (ret==0)
regs->pc += rm + 4;
}
else if ((instruction&0x00FF)==0x0003) {
/* bsrf @Rm */
ret = handle_delayslot(regs, instruction, ma);
if (ret==0) {
regs->pr = regs->pc + 4;
regs->pc += rm + 4;
}
}
else {
/* mov.[bwl] to/from memory via r0+rn */
goto simple;
}
break;
case 0x1000: /* mov.l Rm,@(disp,Rn) */
goto simple;
case 0x2000: /* mov.[bwl] to memory, possibly with pre-decrement */
goto simple;
case 0x4000:
if ((instruction&0x00FF)==0x002B) {
/* jmp @Rm */
ret = handle_delayslot(regs, instruction, ma);
if (ret==0)
regs->pc = rm;
}
else if ((instruction&0x00FF)==0x000B) {
/* jsr @Rm */
ret = handle_delayslot(regs, instruction, ma);
if (ret==0) {
regs->pr = regs->pc + 4;
regs->pc = rm;
}
}
else {
/* mov.[bwl] to/from memory via r0+rn */
goto simple;
}
break;
case 0x5000: /* mov.l @(disp,Rm),Rn */
goto simple;
case 0x6000: /* mov.[bwl] from memory, possibly with post-increment */
goto simple;
case 0x8000: /* bf lab, bf/s lab, bt lab, bt/s lab */
switch (instruction&0x0F00) {
case 0x0100: /* mov.w R0,@(disp,Rm) */
goto simple;
case 0x0500: /* mov.w @(disp,Rm),R0 */
goto simple;
case 0x0B00: /* bf lab - no delayslot*/
ret = 0;
break;
case 0x0F00: /* bf/s lab */
ret = handle_delayslot(regs, instruction, ma);
if (ret==0) {
#if defined(CONFIG_CPU_SH4) || defined(CONFIG_SH7705_CACHE_32KB)
if ((regs->sr & 0x00000001) != 0)
regs->pc += 4; /* next after slot */
else
#endif
regs->pc += SH_PC_8BIT_OFFSET(instruction);
}
break;
case 0x0900: /* bt lab - no delayslot */
ret = 0;
break;
case 0x0D00: /* bt/s lab */
ret = handle_delayslot(regs, instruction, ma);
if (ret==0) {
#if defined(CONFIG_CPU_SH4) || defined(CONFIG_SH7705_CACHE_32KB)
if ((regs->sr & 0x00000001) == 0)
regs->pc += 4; /* next after slot */
else
#endif
regs->pc += SH_PC_8BIT_OFFSET(instruction);
}
break;
}
break;
case 0x9000: /* mov.w @(disp,Rm),Rn */
goto simple;
case 0xA000: /* bra label */
ret = handle_delayslot(regs, instruction, ma);
if (ret==0)
regs->pc += SH_PC_12BIT_OFFSET(instruction);
break;
case 0xB000: /* bsr label */
ret = handle_delayslot(regs, instruction, ma);
if (ret==0) {
regs->pr = regs->pc + 4;
regs->pc += SH_PC_12BIT_OFFSET(instruction);
}
break;
case 0xD000: /* mov.l @(disp,Rm),Rn */
goto simple;
}
return ret;
/* handle non-delay-slot instruction */
simple:
ret = handle_unaligned_ins(instruction, regs, ma);
if (ret==0)
regs->pc += instruction_size(instruction);
return ret;
}
/*
* Handle various address error exceptions:
* - instruction address error:
* misaligned PC
* PC >= 0x80000000 in user mode
* - data address error (read and write)
* misaligned data access
* access to >= 0x80000000 is user mode
* Unfortuntaly we can't distinguish between instruction address error
* and data address errors caused by read accesses.
*/
asmlinkage void do_address_error(struct pt_regs *regs,
unsigned long writeaccess,
unsigned long address)
{
unsigned long error_code = 0;
mm_segment_t oldfs;
siginfo_t info;
insn_size_t instruction;
int tmp;
/* Intentional ifdef */
#ifdef CONFIG_CPU_HAS_SR_RB
error_code = lookup_exception_vector();
#endif
oldfs = get_fs();
if (user_mode(regs)) {
int si_code = BUS_ADRERR;
unsigned int user_action;
local_irq_enable();
inc_unaligned_user_access();
set_fs(USER_DS);
if (copy_from_user(&instruction, (insn_size_t *)(regs->pc & ~1),
sizeof(instruction))) {
set_fs(oldfs);
goto uspace_segv;
}
set_fs(oldfs);
/* shout about userspace fixups */
unaligned_fixups_notify(current, instruction, regs);
user_action = unaligned_user_action();
if (user_action & UM_FIXUP)
goto fixup;
if (user_action & UM_SIGNAL)
goto uspace_segv;
else {
/* ignore */
regs->pc += instruction_size(instruction);
return;
}
fixup:
/* bad PC is not something we can fix */
if (regs->pc & 1) {
si_code = BUS_ADRALN;
goto uspace_segv;
}
set_fs(USER_DS);
tmp = handle_unaligned_access(instruction, regs,
&user_mem_access, 0,
address);
set_fs(oldfs);
if (tmp == 0)
return; /* sorted */
uspace_segv:
printk(KERN_NOTICE "Sending SIGBUS to \"%s\" due to unaligned "
"access (PC %lx PR %lx)\n", current->comm, regs->pc,
regs->pr);
info.si_signo = SIGBUS;
info.si_errno = 0;
info.si_code = si_code;
info.si_addr = (void __user *)address;
force_sig_info(SIGBUS, &info, current);
} else {
inc_unaligned_kernel_access();
if (regs->pc & 1)
die("unaligned program counter", regs, error_code);
set_fs(KERNEL_DS);
if (copy_from_user(&instruction, (void __user *)(regs->pc),
sizeof(instruction))) {
/* Argh. Fault on the instruction itself.
This should never happen non-SMP
*/
set_fs(oldfs);
die("insn faulting in do_address_error", regs, 0);
}
unaligned_fixups_notify(current, instruction, regs);
handle_unaligned_access(instruction, regs, &user_mem_access,
0, address);
set_fs(oldfs);
}
}
#ifdef CONFIG_SH_DSP
/*
* SH-DSP support gerg@snapgear.com.
*/
int is_dsp_inst(struct pt_regs *regs)
{
unsigned short inst = 0;
/*
* Safe guard if DSP mode is already enabled or we're lacking
* the DSP altogether.
*/
if (!(current_cpu_data.flags & CPU_HAS_DSP) || (regs->sr & SR_DSP))
return 0;
get_user(inst, ((unsigned short *) regs->pc));
inst &= 0xf000;
/* Check for any type of DSP or support instruction */
if ((inst == 0xf000) || (inst == 0x4000))
return 1;
return 0;
}
#else
#define is_dsp_inst(regs) (0)
#endif /* CONFIG_SH_DSP */
#ifdef CONFIG_CPU_SH2A
asmlinkage void do_divide_error(unsigned long r4, unsigned long r5,
unsigned long r6, unsigned long r7,
struct pt_regs __regs)
{
siginfo_t info;
switch (r4) {
case TRAP_DIVZERO_ERROR:
info.si_code = FPE_INTDIV;
break;
case TRAP_DIVOVF_ERROR:
info.si_code = FPE_INTOVF;
break;
}
force_sig_info(SIGFPE, &info, current);
}
#endif
asmlinkage void do_reserved_inst(unsigned long r4, unsigned long r5,
unsigned long r6, unsigned long r7,
struct pt_regs __regs)
{
struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
unsigned long error_code;
struct task_struct *tsk = current;
#ifdef CONFIG_SH_FPU_EMU
unsigned short inst = 0;
int err;
get_user(inst, (unsigned short*)regs->pc);
err = do_fpu_inst(inst, regs);
if (!err) {
regs->pc += instruction_size(inst);
return;
}
/* not a FPU inst. */
#endif
#ifdef CONFIG_SH_DSP
/* Check if it's a DSP instruction */
if (is_dsp_inst(regs)) {
/* Enable DSP mode, and restart instruction. */
regs->sr |= SR_DSP;
/* Save DSP mode */
tsk->thread.dsp_status.status |= SR_DSP;
return;
}
#endif
error_code = lookup_exception_vector();
local_irq_enable();
force_sig(SIGILL, tsk);
die_if_no_fixup("reserved instruction", regs, error_code);
}
#ifdef CONFIG_SH_FPU_EMU
static int emulate_branch(unsigned short inst, struct pt_regs *regs)
{
/*
* bfs: 8fxx: PC+=d*2+4;
* bts: 8dxx: PC+=d*2+4;
* bra: axxx: PC+=D*2+4;
* bsr: bxxx: PC+=D*2+4 after PR=PC+4;
* braf:0x23: PC+=Rn*2+4;
* bsrf:0x03: PC+=Rn*2+4 after PR=PC+4;
* jmp: 4x2b: PC=Rn;
* jsr: 4x0b: PC=Rn after PR=PC+4;
* rts: 000b: PC=PR;
*/
if (((inst & 0xf000) == 0xb000) || /* bsr */
((inst & 0xf0ff) == 0x0003) || /* bsrf */
((inst & 0xf0ff) == 0x400b)) /* jsr */
regs->pr = regs->pc + 4;
if ((inst & 0xfd00) == 0x8d00) { /* bfs, bts */
regs->pc += SH_PC_8BIT_OFFSET(inst);
return 0;
}
if ((inst & 0xe000) == 0xa000) { /* bra, bsr */
regs->pc += SH_PC_12BIT_OFFSET(inst);
return 0;
}
if ((inst & 0xf0df) == 0x0003) { /* braf, bsrf */
regs->pc += regs->regs[(inst & 0x0f00) >> 8] + 4;
return 0;
}
if ((inst & 0xf0df) == 0x400b) { /* jmp, jsr */
regs->pc = regs->regs[(inst & 0x0f00) >> 8];
return 0;
}
if ((inst & 0xffff) == 0x000b) { /* rts */
regs->pc = regs->pr;
return 0;
}
return 1;
}
#endif
asmlinkage void do_illegal_slot_inst(unsigned long r4, unsigned long r5,
unsigned long r6, unsigned long r7,
struct pt_regs __regs)
{
struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
unsigned long inst;
struct task_struct *tsk = current;
if (kprobe_handle_illslot(regs->pc) == 0)
return;
#ifdef CONFIG_SH_FPU_EMU
get_user(inst, (unsigned short *)regs->pc + 1);
if (!do_fpu_inst(inst, regs)) {
get_user(inst, (unsigned short *)regs->pc);
if (!emulate_branch(inst, regs))
return;
/* fault in branch.*/
}
/* not a FPU inst. */
#endif
inst = lookup_exception_vector();
local_irq_enable();
force_sig(SIGILL, tsk);
die_if_no_fixup("illegal slot instruction", regs, inst);
}
asmlinkage void do_exception_error(unsigned long r4, unsigned long r5,
unsigned long r6, unsigned long r7,
struct pt_regs __regs)
{
struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
long ex;
ex = lookup_exception_vector();
die_if_kernel("exception", regs, ex);
}
void per_cpu_trap_init(void)
{
extern void *vbr_base;
/* NOTE: The VBR value should be at P1
(or P2, virtural "fixed" address space).
It's definitely should not in physical address. */
asm volatile("ldc %0, vbr"
: /* no output */
: "r" (&vbr_base)
: "memory");
/* disable exception blocking now when the vbr has been setup */
clear_bl_bit();
}
void *set_exception_table_vec(unsigned int vec, void *handler)
{
extern void *exception_handling_table[];
void *old_handler;
old_handler = exception_handling_table[vec];
exception_handling_table[vec] = handler;
return old_handler;
}
void __init trap_init(void)
{
set_exception_table_vec(TRAP_RESERVED_INST, do_reserved_inst);
set_exception_table_vec(TRAP_ILLEGAL_SLOT_INST, do_illegal_slot_inst);
#if defined(CONFIG_CPU_SH4) && !defined(CONFIG_SH_FPU) || \
defined(CONFIG_SH_FPU_EMU)
/*
* For SH-4 lacking an FPU, treat floating point instructions as
* reserved. They'll be handled in the math-emu case, or faulted on
* otherwise.
*/
set_exception_table_evt(0x800, do_reserved_inst);
set_exception_table_evt(0x820, do_illegal_slot_inst);
#elif defined(CONFIG_SH_FPU)
set_exception_table_evt(0x800, fpu_state_restore_trap_handler);
set_exception_table_evt(0x820, fpu_state_restore_trap_handler);
#endif
#ifdef CONFIG_CPU_SH2
set_exception_table_vec(TRAP_ADDRESS_ERROR, address_error_trap_handler);
#endif
#ifdef CONFIG_CPU_SH2A
set_exception_table_vec(TRAP_DIVZERO_ERROR, do_divide_error);
set_exception_table_vec(TRAP_DIVOVF_ERROR, do_divide_error);
#ifdef CONFIG_SH_FPU
set_exception_table_vec(TRAP_FPU_ERROR, fpu_error_trap_handler);
#endif
#endif
#ifdef TRAP_UBC
set_exception_table_vec(TRAP_UBC, breakpoint_trap_handler);
#endif
}
View git blame Copy permalink