From 19eadf98c8167eac843580683317b99572e2abf0 Mon Sep 17 00:00:00 2001 From: Rusty Russell Date: Tue, 27 Jun 2006 02:53:44 -0700 Subject: [PATCH] [PATCH] x86: increase interrupt vector range Remove the limit of 256 interrupt vectors by changing the value stored in orig_{e,r}ax to be the complemented interrupt vector. The orig_{e,r}ax needs to be < 0 to allow the signal code to distinguish between return from interrupt and return from syscall. With this change applied, NR_IRQS can be > 256. Xen extends the IRQ numbering space to include room for dynamically allocated virtual interrupts (in the range 256-511), which requires a more permissive interface to do_IRQ. Signed-off-by: Ian Pratt Signed-off-by: Christian Limpach Signed-off-by: Chris Wright Signed-off-by: Rusty Russell Cc: "Protasevich, Natalie" Cc: Andi Kleen Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/i386/kernel/entry.S | 4 ++-- arch/i386/kernel/irq.c | 4 ++-- arch/x86_64/kernel/entry.S | 2 +- arch/x86_64/kernel/irq.c | 4 ++-- arch/x86_64/kernel/smp.c | 4 ++-- include/asm-x86_64/hw_irq.h | 2 +- 6 files changed, 10 insertions(+), 10 deletions(-) diff --git a/arch/i386/kernel/entry.S b/arch/i386/kernel/entry.S index e6e4506e749a..8713e0248a0b 100644 --- a/arch/i386/kernel/entry.S +++ b/arch/i386/kernel/entry.S @@ -515,7 +515,7 @@ ENTRY(irq_entries_start) .if vector CFI_ADJUST_CFA_OFFSET -4 .endif -1: pushl $vector-256 +1: pushl $~(vector) CFI_ADJUST_CFA_OFFSET 4 jmp common_interrupt .data @@ -535,7 +535,7 @@ common_interrupt: #define BUILD_INTERRUPT(name, nr) \ ENTRY(name) \ RING0_INT_FRAME; \ - pushl $nr-256; \ + pushl $~(nr); \ CFI_ADJUST_CFA_OFFSET 4; \ SAVE_ALL; \ movl %esp,%eax; \ diff --git a/arch/i386/kernel/irq.c b/arch/i386/kernel/irq.c index 061533e0cb5e..586b15f6741f 100644 --- a/arch/i386/kernel/irq.c +++ b/arch/i386/kernel/irq.c @@ -53,8 +53,8 @@ static union irq_ctx *softirq_ctx[NR_CPUS] __read_mostly; */ fastcall unsigned int do_IRQ(struct pt_regs *regs) { - /* high bits used in ret_from_ code */ - int irq = regs->orig_eax & 0xff; + /* high bit used in ret_from_ code */ + int irq = ~regs->orig_eax; #ifdef CONFIG_4KSTACKS union irq_ctx *curctx, *irqctx; u32 *isp; diff --git a/arch/x86_64/kernel/entry.S b/arch/x86_64/kernel/entry.S index 7290e72b9a34..22cac4487b57 100644 --- a/arch/x86_64/kernel/entry.S +++ b/arch/x86_64/kernel/entry.S @@ -588,7 +588,7 @@ END(common_interrupt) */ .macro apicinterrupt num,func INTR_FRAME - pushq $\num-256 + pushq $~(\num) CFI_ADJUST_CFA_OFFSET 8 interrupt \func jmp ret_from_intr diff --git a/arch/x86_64/kernel/irq.c b/arch/x86_64/kernel/irq.c index 59518d4d4358..3be0a7e4bf08 100644 --- a/arch/x86_64/kernel/irq.c +++ b/arch/x86_64/kernel/irq.c @@ -115,8 +115,8 @@ skip: */ asmlinkage unsigned int do_IRQ(struct pt_regs *regs) { - /* high bits used in ret_from_ code */ - unsigned irq = regs->orig_rax & 0xff; + /* high bit used in ret_from_ code */ + unsigned irq = ~regs->orig_rax; exit_idle(); irq_enter(); diff --git a/arch/x86_64/kernel/smp.c b/arch/x86_64/kernel/smp.c index acee4bc3f6fa..5a1c0a3bf872 100644 --- a/arch/x86_64/kernel/smp.c +++ b/arch/x86_64/kernel/smp.c @@ -135,10 +135,10 @@ asmlinkage void smp_invalidate_interrupt(struct pt_regs *regs) cpu = smp_processor_id(); /* - * orig_rax contains the interrupt vector - 256. + * orig_rax contains the negated interrupt vector. * Use that to determine where the sender put the data. */ - sender = regs->orig_rax + 256 - INVALIDATE_TLB_VECTOR_START; + sender = ~regs->orig_rax - INVALIDATE_TLB_VECTOR_START; f = &per_cpu(flush_state, sender); if (!cpu_isset(cpu, f->flush_cpumask)) diff --git a/include/asm-x86_64/hw_irq.h b/include/asm-x86_64/hw_irq.h index 1b2ac55d3204..931877462788 100644 --- a/include/asm-x86_64/hw_irq.h +++ b/include/asm-x86_64/hw_irq.h @@ -124,7 +124,7 @@ asmlinkage void IRQ_NAME(nr); \ __asm__( \ "\n.p2align\n" \ "IRQ" #nr "_interrupt:\n\t" \ - "push $" #nr "-256 ; " \ + "push $~(" #nr ") ; " \ "jmp common_interrupt"); #if defined(CONFIG_X86_IO_APIC) -- 2.39.5