From: Rusty Russell <rusty@rustcorp.com.au>
This simplifies the io_apic.c __assign_irq_vector() logic and removes
the explicit SYSCALL_VECTOR check, and also allows for vectors to be
reserved by other mechanisms (ie. lguest).
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andi Kleen <ak@suse.de>
---
arch/i386/kernel/i8259.c | 3 ++-
arch/i386/kernel/io_apic.c | 13 ++++++++-----
arch/i386/kernel/traps.c | 10 ++++++++++
include/asm-i386/irq.h | 3 +++
4 files changed, 23 insertions(+), 6 deletions(-)
===================================================================
Index: linux/arch/i386/kernel/i8259.c
===================================================================
--- linux.orig/arch/i386/kernel/i8259.c
+++ linux/arch/i386/kernel/i8259.c
@@ -400,7 +400,8 @@ void __init native_init_IRQ(void)
int vector = FIRST_EXTERNAL_VECTOR + i;
if (i >= NR_IRQS)
break;
- if (vector != SYSCALL_VECTOR)
+ /* SYSCALL_VECTOR was reserved in trap_init. */
+ if (!test_bit(vector, used_vectors))
set_intr_gate(vector, interrupt[i]);
}
Index: linux/arch/i386/kernel/io_apic.c
===================================================================
--- linux.orig/arch/i386/kernel/io_apic.c
+++ linux/arch/i386/kernel/io_apic.c
@@ -1198,7 +1198,7 @@ static u8 irq_vector[NR_IRQ_VECTORS] __r
static int __assign_irq_vector(int irq)
{
static int current_vector = FIRST_DEVICE_VECTOR, current_offset = 0;
- int vector, offset, i;
+ int vector, offset;
BUG_ON((unsigned)irq >= NR_IRQ_VECTORS);
@@ -1215,11 +1215,8 @@ next:
}
if (vector == current_vector)
return -ENOSPC;
- if (vector == SYSCALL_VECTOR)
+ if (test_and_set_bit(vector, used_vectors))
goto next;
- for (i = 0; i < NR_IRQ_VECTORS; i++)
- if (irq_vector[i] == vector)
- goto next;
current_vector = vector;
current_offset = offset;
@@ -2290,6 +2287,12 @@ static inline void __init check_timer(vo
void __init setup_IO_APIC(void)
{
+ int i;
+
+ /* Reserve all the system vectors. */
+ for (i = FIRST_SYSTEM_VECTOR; i < NR_VECTORS; i++)
+ set_bit(i, used_vectors);
+
enable_IO_APIC();
if (acpi_ioapic)
Index: linux/arch/i386/kernel/traps.c
===================================================================
--- linux.orig/arch/i386/kernel/traps.c
+++ linux/arch/i386/kernel/traps.c
@@ -65,6 +65,9 @@
int panic_on_unrecovered_nmi;
+DECLARE_BITMAP(used_vectors, NR_VECTORS);
+EXPORT_SYMBOL_GPL(used_vectors);
+
asmlinkage int system_call(void);
/* Do we ignore FPU interrupts ? */
@@ -1217,6 +1220,8 @@ static void __init set_task_gate(unsigne
void __init trap_init(void)
{
+ int i;
+
#ifdef CONFIG_EISA
void __iomem *p = ioremap(0x0FFFD9, 4);
if (readl(p) == 'E'+('I'<<8)+('S'<<16)+('A'<<24)) {
@@ -1276,6 +1281,11 @@ void __init trap_init(void)
set_system_gate(SYSCALL_VECTOR,&system_call);
+ /* Reserve all the builtin and the syscall vector. */
+ for (i = 0; i < FIRST_EXTERNAL_VECTOR; i++)
+ set_bit(i, used_vectors);
+ set_bit(SYSCALL_VECTOR, used_vectors);
+
/*
* Should be a barrier for any external CPU state.
*/
Index: linux/include/asm-i386/irq.h
===================================================================
--- linux.orig/include/asm-i386/irq.h
+++ linux/include/asm-i386/irq.h
@@ -45,4 +45,7 @@ unsigned int do_IRQ(struct pt_regs *regs
void init_IRQ(void);
void __init native_init_IRQ(void);
+/* Interrupt vector management */
+extern DECLARE_BITMAP(used_vectors, NR_VECTORS);
+
#endif /* _ASM_IRQ_H */
-
