[PATCH 2/2] x86: Change trap definitions to enumerated values

From: Vaibhav Nagarnaik
Date: Fri Apr 22 2011 - 19:04:36 EST


From: Aditya Kali <adityakali@xxxxxxxxxx>

The traps are referred to by their numbers and it can be difficult to
understand them while reading the code without context. This patch adds
enumeration of the trap numbers and replaced the numbers to the correct
enum for x86.

Signed-off-by: Vaibhav Nagarnaik <vnagarnaik@xxxxxxxxxx>
---
arch/x86/include/asm/traps.h | 24 ++++++++
arch/x86/kernel/traps.c | 129 +++++++++++++++++++++++-------------------
2 files changed, 94 insertions(+), 59 deletions(-)

diff --git a/arch/x86/include/asm/traps.h b/arch/x86/include/asm/traps.h
index 0310da6..c561caf 100644
--- a/arch/x86/include/asm/traps.h
+++ b/arch/x86/include/asm/traps.h
@@ -87,4 +87,28 @@ asmlinkage void smp_thermal_interrupt(void);
asmlinkage void mce_threshold_interrupt(void);
#endif

+/* Interrupts/Exceptions */
+enum {
+ INTR_DIV_BY_ZERO = 0, /* 0 */
+ INTR_DEBUG, /* 1 */
+ INTR_NMI, /* 2 */
+ INTR_BREAKPOINT, /* 3 */
+ INTR_OVERFLOW, /* 4 */
+ INTR_BOUNDS_CHECK, /* 5 */
+ INTR_INVALID_OP, /* 6 */
+ INTR_NO_DEV, /* 7 */
+ INTR_DBL_FAULT, /* 8 */
+ INTR_SEG_OVERRUN, /* 9 */
+ INTR_INVALID_TSS, /* 10 */
+ INTR_NO_SEG, /* 11 */
+ INTR_STACK_FAULT, /* 12 */
+ INTR_GPF, /* 13 */
+ INTR_PAGE_FAULT, /* 14 */
+ INTR_SPURIOUS, /* 15 */
+ INTR_COPROCESSOR, /* 16 */
+ INTR_ALIGNMENT, /* 17 */
+ INTR_MCE, /* 18 */
+ INTR_SIMD_COPROCESSOR /* 19 */
+};
+
#endif /* _ASM_X86_TRAPS_H */
diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c
index d450349..f6c5276 100644
--- a/arch/x86/kernel/traps.c
+++ b/arch/x86/kernel/traps.c
@@ -133,7 +133,7 @@ do_trap(int trapnr, int signr, char *str, struct pt_regs *regs,
* traps 0, 1, 3, 4, and 5 should be forwarded to vm86.
* On nmi (interrupt 2), do_trap should not be called.
*/
- if (trapnr < 6)
+ if (trapnr < INTR_INVALID_OP)
goto vm86_trap;
goto trap_signal;
}
@@ -220,27 +220,32 @@ dotraplinkage void do_##name(struct pt_regs *regs, long error_code) \
do_trap(trapnr, signr, str, regs, error_code, &info); \
}

-DO_ERROR_INFO(0, SIGFPE, "divide error", divide_error, FPE_INTDIV, regs->ip)
-DO_ERROR(4, SIGSEGV, "overflow", overflow)
-DO_ERROR(5, SIGSEGV, "bounds", bounds)
-DO_ERROR_INFO(6, SIGILL, "invalid opcode", invalid_op, ILL_ILLOPN, regs->ip)
-DO_ERROR(9, SIGFPE, "coprocessor segment overrun", coprocessor_segment_overrun)
-DO_ERROR(10, SIGSEGV, "invalid TSS", invalid_TSS)
-DO_ERROR(11, SIGBUS, "segment not present", segment_not_present)
+DO_ERROR_INFO(INTR_DIV_BY_ZERO, SIGFPE, "divide error", divide_error,
+ FPE_INTDIV, regs->ip)
+DO_ERROR(INTR_OVERFLOW, SIGSEGV, "overflow", overflow)
+DO_ERROR(INTR_BOUNDS_CHECK, SIGSEGV, "bounds", bounds)
+DO_ERROR_INFO(INTR_INVALID_OP, SIGILL, "invalid opcode", invalid_op,
+ ILL_ILLOPN, regs->ip)
+DO_ERROR(INTR_SEG_OVERRUN, SIGFPE, "coprocessor segment overrun",
+ coprocessor_segment_overrun)
+DO_ERROR(INTR_INVALID_TSS, SIGSEGV, "invalid TSS", invalid_TSS)
+DO_ERROR(INTR_NO_SEG, SIGBUS, "segment not present", segment_not_present)
#ifdef CONFIG_X86_32
-DO_ERROR(12, SIGBUS, "stack segment", stack_segment)
+DO_ERROR(INTR_STACK_FAULT, SIGBUS, "stack segment", stack_segment)
#endif
-DO_ERROR_INFO(17, SIGBUS, "alignment check", alignment_check, BUS_ADRALN, 0)
+DO_ERROR_INFO(INTR_ALIGNMENT, SIGBUS, "alignment check", alignment_check,
+ BUS_ADRALN, 0)

#ifdef CONFIG_X86_64
/* Runs on IST stack */
dotraplinkage void do_stack_segment(struct pt_regs *regs, long error_code)
{
if (notify_die(DIE_TRAP, "stack segment", regs, error_code,
- 12, SIGBUS) == NOTIFY_STOP)
+ INTR_STACK_FAULT, SIGBUS) == NOTIFY_STOP)
return;
preempt_conditional_sti(regs);
- do_trap(12, SIGBUS, "stack segment", regs, error_code, NULL);
+ do_trap(INTR_STACK_FAULT, SIGBUS, "stack segment", regs, error_code,
+ NULL);
preempt_conditional_cli(regs);
}

@@ -250,10 +255,10 @@ dotraplinkage void do_double_fault(struct pt_regs *regs, long error_code)
struct task_struct *tsk = current;

/* Return not checked because double check cannot be ignored */
- notify_die(DIE_TRAP, str, regs, error_code, 8, SIGSEGV);
+ notify_die(DIE_TRAP, str, regs, error_code, INTR_DBL_FAULT, SIGSEGV);

tsk->thread.error_code = error_code;
- tsk->thread.trap_no = 8;
+ tsk->thread.trap_no = INTR_DBL_FAULT;

/*
* This is always a kernel trap and never fixable (and thus must
@@ -281,7 +286,7 @@ do_general_protection(struct pt_regs *regs, long error_code)
goto gp_in_kernel;

tsk->thread.error_code = error_code;
- tsk->thread.trap_no = 13;
+ tsk->thread.trap_no = INTR_GPF;

if (show_unhandled_signals && unhandled_signal(tsk, SIGSEGV) &&
printk_ratelimit()) {
@@ -310,9 +315,9 @@ gp_in_kernel:
return;

tsk->thread.error_code = error_code;
- tsk->thread.trap_no = 13;
+ tsk->thread.trap_no = INTR_GPF;
if (notify_die(DIE_GPF, "general protection fault", regs,
- error_code, 13, SIGSEGV) == NOTIFY_STOP)
+ error_code, INTR_GPF, SIGSEGV) == NOTIFY_STOP)
return;
die("general protection fault", regs, error_code);
}
@@ -381,7 +386,8 @@ io_check_error(unsigned char reason, struct pt_regs *regs)
static notrace __kprobes void
unknown_nmi_error(unsigned char reason, struct pt_regs *regs)
{
- if (notify_die(DIE_NMIUNKNOWN, "nmi", regs, reason, 2, SIGINT) ==
+ if (notify_die(DIE_NMIUNKNOWN, "nmi", regs, reason, INTR_NMI,
+ SIGINT) ==
NOTIFY_STOP)
return;
#ifdef CONFIG_MCA
@@ -413,7 +419,8 @@ static notrace __kprobes void default_do_nmi(struct pt_regs *regs)
* NMI, otherwise we may lose it, because the CPU-specific
* NMI can not be detected/processed on other CPUs.
*/
- if (notify_die(DIE_NMI, "nmi", regs, 0, 2, SIGINT) == NOTIFY_STOP)
+ if (notify_die(DIE_NMI, "nmi", regs, 0, INTR_NMI, SIGINT) ==
+ NOTIFY_STOP)
return;

/* Non-CPU-specific NMI: NMI sources can be processed on any CPU */
@@ -469,22 +476,24 @@ void restart_nmi(void)
dotraplinkage void __kprobes do_int3(struct pt_regs *regs, long error_code)
{
#ifdef CONFIG_KGDB_LOW_LEVEL_TRAP
- if (kgdb_ll_trap(DIE_INT3, "int3", regs, error_code, 3, SIGTRAP)
- == NOTIFY_STOP)
+ if (kgdb_ll_trap(DIE_INT3, "int3", regs, error_code, INTR_BREAKPOINT,
+ SIGTRAP) == NOTIFY_STOP)
return;
#endif /* CONFIG_KGDB_LOW_LEVEL_TRAP */
#ifdef CONFIG_KPROBES
- if (notify_die(DIE_INT3, "int3", regs, error_code, 3, SIGTRAP)
+ if (notify_die(DIE_INT3, "int3", regs, error_code, INTR_BREAKPOINT,
+ SIGTRAP)
== NOTIFY_STOP)
return;
#else
- if (notify_die(DIE_TRAP, "int3", regs, error_code, 3, SIGTRAP)
+ if (notify_die(DIE_TRAP, "int3", regs, error_code, INTR_BREAKPOINT,
+ SIGTRAP)
== NOTIFY_STOP)
return;
#endif

preempt_conditional_sti(regs);
- do_trap(3, SIGTRAP, "int3", regs, error_code, NULL);
+ do_trap(INTR_BREAKPOINT, SIGTRAP, "int3", regs, error_code, NULL);
preempt_conditional_cli(regs);
}

@@ -583,7 +592,7 @@ dotraplinkage void __kprobes do_debug(struct pt_regs *regs, long error_code)

if (regs->flags & X86_VM_MASK) {
handle_vm86_trap((struct kernel_vm86_regs *) regs,
- error_code, 1);
+ error_code, INTR_DEBUG);
preempt_conditional_cli(regs);
return;
}
@@ -611,14 +620,15 @@ dotraplinkage void __kprobes do_debug(struct pt_regs *regs, long error_code)
/*
* Note that we play around with the 'TS' bit in an attempt to get
* the correct behaviour even in the presence of the asynchronous
- * IRQ13 behaviour
+ * INTR_GPF behaviour
*/
void math_error(struct pt_regs *regs, int error_code, int trapnr)
{
struct task_struct *task = current;
siginfo_t info;
unsigned short err;
- char *str = (trapnr == 16) ? "fpu exception" : "simd exception";
+ char *str = (trapnr == INTR_COPROCESSOR) ? "fpu exception" :
+ "simd exception";

if (notify_die(DIE_TRAP, str, regs, error_code, trapnr, SIGFPE) == NOTIFY_STOP)
return;
@@ -643,7 +653,7 @@ void math_error(struct pt_regs *regs, int error_code, int trapnr)
info.si_signo = SIGFPE;
info.si_errno = 0;
info.si_addr = (void __user *)regs->ip;
- if (trapnr == 16) {
+ if (trapnr == INTR_COPROCESSOR) {
unsigned short cwd, swd;
/*
* (~cwd & swd) will mask out exceptions that are not set to unmasked
@@ -687,8 +697,9 @@ void math_error(struct pt_regs *regs, int error_code, int trapnr)
info.si_code = FPE_FLTRES;
} else {
/*
- * If we're using IRQ 13, or supposedly even some trap 16
- * implementations, it's possible we get a spurious trap...
+ * If we're using INTR_GPF, or supposedly even some trap
+ * INTR_COPROCESSOR implementations, it's possible we get a
+ * spurious trap...
*/
return; /* Spurious trap, no error */
}
@@ -703,25 +714,25 @@ dotraplinkage void do_coprocessor_error(struct pt_regs *regs, long error_code)
ignore_fpu_irq = 1;
#endif

- math_error(regs, error_code, 16);
+ math_error(regs, error_code, INTR_COPROCESSOR);
}

dotraplinkage void
do_simd_coprocessor_error(struct pt_regs *regs, long error_code)
{
- math_error(regs, error_code, 19);
+ math_error(regs, error_code, INTR_SIMD_COPROCESSOR);
}

dotraplinkage void
do_spurious_interrupt_bug(struct pt_regs *regs, long error_code)
{
- trace_trap_entry(15);
+ trace_trap_entry(INTR_SPURIOUS);
conditional_sti(regs);
#if 0
/* No need to warn about this any longer. */
printk(KERN_INFO "Ignoring P6 Local APIC Spurious Interrupt Bug...\n");
#endif
- trace_trap_exit(15);
+ trace_trap_exit(INTR_SPURIOUS);
}

asmlinkage void __attribute__((weak)) smp_thermal_interrupt(void)
@@ -758,7 +769,7 @@ void __math_state_restore(void)
* 'math_state_restore()' saves the current math information in the
* old math state array, and gets the new ones from the current task
*
- * Careful.. There are problems with IBM-designed IRQ13 behaviour.
+ * Careful.. There are problems with IBM-designed INTR_GPF behaviour.
* Don't touch unless you *really* know how it works.
*
* Must be called with kernel preemption disabled (in this case,
@@ -793,7 +804,7 @@ EXPORT_SYMBOL_GPL(math_state_restore);
dotraplinkage void __kprobes
do_device_not_available(struct pt_regs *regs, long error_code)
{
- trace_trap_entry(7);
+ trace_trap_entry(INTR_NO_DEV);
#ifdef CONFIG_MATH_EMULATION
if (read_cr0() & X86_CR0_EM) {
struct math_emu_info info = { };
@@ -802,7 +813,7 @@ do_device_not_available(struct pt_regs *regs, long error_code)

info.regs = regs;
math_emulate(&info);
- trace_trap_exit(7);
+ trace_trap_exit(INTR_NO_DEV);
return;
}
#endif
@@ -810,7 +821,7 @@ do_device_not_available(struct pt_regs *regs, long error_code)
#ifdef CONFIG_X86_32
conditional_sti(regs);
#endif
- trace_trap_exit(7);
+ trace_trap_exit(INTR_NO_DEV);
}

#ifdef CONFIG_X86_32
@@ -833,10 +844,10 @@ dotraplinkage void do_iret_error(struct pt_regs *regs, long error_code)
/* Set of traps needed for early debugging. */
void __init early_trap_init(void)
{
- set_intr_gate_ist(1, &debug, DEBUG_STACK);
+ set_intr_gate_ist(INTR_DEBUG, &debug, DEBUG_STACK);
/* int3 can be called from all */
- set_system_intr_gate_ist(3, &int3, DEBUG_STACK);
- set_intr_gate(14, &page_fault);
+ set_system_intr_gate_ist(INTR_BREAKPOINT, &int3, DEBUG_STACK);
+ set_intr_gate(INTR_PAGE_FAULT, &page_fault);
load_idt(&idt_descr);
}

@@ -852,30 +863,30 @@ void __init trap_init(void)
early_iounmap(p, 4);
#endif

- set_intr_gate(0, &divide_error);
- set_intr_gate_ist(2, &nmi, NMI_STACK);
+ set_intr_gate(INTR_DIV_BY_ZERO, &divide_error);
+ set_intr_gate_ist(INTR_NMI, &nmi, NMI_STACK);
/* int4 can be called from all */
- set_system_intr_gate(4, &overflow);
- set_intr_gate(5, &bounds);
- set_intr_gate(6, &invalid_op);
- set_intr_gate(7, &device_not_available);
+ set_system_intr_gate(INTR_OVERFLOW, &overflow);
+ set_intr_gate(INTR_BOUNDS_CHECK, &bounds);
+ set_intr_gate(INTR_INVALID_OP, &invalid_op);
+ set_intr_gate(INTR_NO_DEV, &device_not_available);
#ifdef CONFIG_X86_32
- set_task_gate(8, GDT_ENTRY_DOUBLEFAULT_TSS);
+ set_task_gate(INTR_DBL_FAULT, GDT_ENTRY_DOUBLEFAULT_TSS);
#else
- set_intr_gate_ist(8, &double_fault, DOUBLEFAULT_STACK);
+ set_intr_gate_ist(INTR_DBL_FAULT, &double_fault, DOUBLEFAULT_STACK);
#endif
- set_intr_gate(9, &coprocessor_segment_overrun);
- set_intr_gate(10, &invalid_TSS);
- set_intr_gate(11, &segment_not_present);
- set_intr_gate_ist(12, &stack_segment, STACKFAULT_STACK);
- set_intr_gate(13, &general_protection);
- set_intr_gate(15, &spurious_interrupt_bug);
- set_intr_gate(16, &coprocessor_error);
- set_intr_gate(17, &alignment_check);
+ set_intr_gate(INTR_SEG_OVERRUN, &coprocessor_segment_overrun);
+ set_intr_gate(INTR_INVALID_TSS, &invalid_TSS);
+ set_intr_gate(INTR_NO_SEG, &segment_not_present);
+ set_intr_gate_ist(INTR_STACK_FAULT, &stack_segment, STACKFAULT_STACK);
+ set_intr_gate(INTR_GPF, &general_protection);
+ set_intr_gate(INTR_SPURIOUS, &spurious_interrupt_bug);
+ set_intr_gate(INTR_COPROCESSOR, &coprocessor_error);
+ set_intr_gate(INTR_ALIGNMENT, &alignment_check);
#ifdef CONFIG_X86_MCE
- set_intr_gate_ist(18, &machine_check, MCE_STACK);
+ set_intr_gate_ist(INTR_MCE, &machine_check, MCE_STACK);
#endif
- set_intr_gate(19, &simd_coprocessor_error);
+ set_intr_gate(INTR_SIMD_COPROCESSOR, &simd_coprocessor_error);

/* Reserve all the builtin and the syscall vector: */
for (i = 0; i < FIRST_EXTERNAL_VECTOR; i++)
--
1.7.3.1

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