From dbeb2be21d678c49a8d8bbf774903df15dd55474 Mon Sep 17 00:00:00 2001 From: Rusty Russell Date: Fri, 19 Oct 2007 20:35:03 +0200 Subject: [PATCH] i386: introduce "used_vectors" bitmap which can be used to reserve vectors. 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). [ tglx: arch/x86 adaptation ] Signed-off-by: Rusty Russell Signed-off-by: Andi Kleen Signed-off-by: Ingo Molnar Signed-off-by: Thomas Gleixner --- arch/x86/kernel/i8259_32.c | 3 ++- arch/x86/kernel/io_apic_32.c | 13 ++++++++----- arch/x86/kernel/traps_32.c | 10 ++++++++++ include/asm-x86/irq_32.h | 3 +++ 4 files changed, 23 insertions(+), 6 deletions(-) diff --git a/arch/x86/kernel/i8259_32.c b/arch/x86/kernel/i8259_32.c index d34a10cc13..f634fc715c 100644 --- a/arch/x86/kernel/i8259_32.c +++ b/arch/x86/kernel/i8259_32.c @@ -403,7 +403,8 @@ 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]); } diff --git a/arch/x86/kernel/io_apic_32.c b/arch/x86/kernel/io_apic_32.c index 5f10c71895..0c55e9d86f 100644 --- a/arch/x86/kernel/io_apic_32.c +++ b/arch/x86/kernel/io_apic_32.c @@ -1198,7 +1198,7 @@ static u8 irq_vector[NR_IRQ_VECTORS] __read_mostly = { FIRST_DEVICE_VECTOR , 0 } 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; @@ -2295,6 +2292,12 @@ static inline void __init check_timer(void) 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) diff --git a/arch/x86/kernel/traps_32.c b/arch/x86/kernel/traps_32.c index 3f02e0f42e..47e6d10902 100644 --- a/arch/x86/kernel/traps_32.c +++ b/arch/x86/kernel/traps_32.c @@ -63,6 +63,9 @@ 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 ? */ @@ -1120,6 +1123,8 @@ static void __init set_task_gate(unsigned int n, unsigned int gdt_entry) 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)) { @@ -1179,6 +1184,11 @@ 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. */ diff --git a/include/asm-x86/irq_32.h b/include/asm-x86/irq_32.h index 36f310632c..aca9c96e8e 100644 --- a/include/asm-x86/irq_32.h +++ b/include/asm-x86/irq_32.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 */ -- 2.39.5