Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760073AbYFYEqW (ORCPT ); Wed, 25 Jun 2008 00:46:22 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753684AbYFYEhn (ORCPT ); Wed, 25 Jun 2008 00:37:43 -0400 Received: from 9.sub-70-198-159.myvzw.com ([70.198.159.9]:37455 "EHLO mail.goop.org" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1755475AbYFYEhZ (ORCPT ); Wed, 25 Jun 2008 00:37:25 -0400 Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: [PATCH 19 of 36] paravirt_ops: define PARA_INDIRECT for indirect asm calls X-Mercurial-Node: 79981976b577491a53643209857aedbbcbbe99c3 Message-Id: <79981976b577491a5364.1214367555@localhost> In-Reply-To: Date: Wed, 25 Jun 2008 00:19:15 -0400 From: Jeremy Fitzhardinge To: Ingo Molnar Cc: LKML , x86@kernel.org, xen-devel , Stephen Tweedie , Eduardo Habkost , Mark McLoughlin , x86@kernel.org Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3464 Lines: 92 On 32-bit it's best to use a %cs: prefix to access memory where the other segments may not bet set up properly yet. On 64-bit it's best to use a rip-relative addressing mode. Define PARA_INDIRECT() to abstract this and generate the proper addressing mode in each case. Signed-off-by: Jeremy Fitzhardinge --- include/asm-x86/paravirt.h | 30 ++++++++++++++++-------------- 1 file changed, 16 insertions(+), 14 deletions(-) diff --git a/include/asm-x86/paravirt.h b/include/asm-x86/paravirt.h --- a/include/asm-x86/paravirt.h +++ b/include/asm-x86/paravirt.h @@ -1456,55 +1456,57 @@ #define PV_RESTORE_REGS popq %rdx; popq %rcx; popq %rdi; popq %rax #define PARA_PATCH(struct, off) ((PARAVIRT_PATCH_##struct + (off)) / 8) #define PARA_SITE(ptype, clobbers, ops) _PVSITE(ptype, clobbers, ops, .quad, 8) +#define PARA_INDIRECT(addr) *addr(%rip) #else #define PV_SAVE_REGS pushl %eax; pushl %edi; pushl %ecx; pushl %edx #define PV_RESTORE_REGS popl %edx; popl %ecx; popl %edi; popl %eax #define PARA_PATCH(struct, off) ((PARAVIRT_PATCH_##struct + (off)) / 4) #define PARA_SITE(ptype, clobbers, ops) _PVSITE(ptype, clobbers, ops, .long, 4) +#define PARA_INDIRECT(addr) *%cs:addr #endif #define INTERRUPT_RETURN \ PARA_SITE(PARA_PATCH(pv_cpu_ops, PV_CPU_iret), CLBR_NONE, \ - jmp *%cs:pv_cpu_ops+PV_CPU_iret) + jmp PARA_INDIRECT(pv_cpu_ops+PV_CPU_iret)) #define INTERRUPT_RETURN_NMI_SAFE \ PARA_SITE(PARA_PATCH(pv_cpu_ops, PV_CPU_nmi_return), CLBR_NONE, \ - jmp *%cs:pv_cpu_ops+PV_CPU_nmi_return) + jmp PARA_INDIRECT(pv_cpu_ops+PV_CPU_nmi_return)) #define DISABLE_INTERRUPTS(clobbers) \ PARA_SITE(PARA_PATCH(pv_irq_ops, PV_IRQ_irq_disable), clobbers, \ - PV_SAVE_REGS; \ - call *%cs:pv_irq_ops+PV_IRQ_irq_disable; \ + PV_SAVE_REGS; \ + call PARA_INDIRECT(pv_irq_ops+PV_IRQ_irq_disable); \ PV_RESTORE_REGS;) \ #define ENABLE_INTERRUPTS(clobbers) \ PARA_SITE(PARA_PATCH(pv_irq_ops, PV_IRQ_irq_enable), clobbers, \ - PV_SAVE_REGS; \ - call *%cs:pv_irq_ops+PV_IRQ_irq_enable; \ + PV_SAVE_REGS; \ + call PARA_INDIRECT(pv_irq_ops+PV_IRQ_irq_enable); \ PV_RESTORE_REGS;) #define ENABLE_INTERRUPTS_SYSCALL_RET \ PARA_SITE(PARA_PATCH(pv_cpu_ops, PV_CPU_irq_enable_syscall_ret),\ CLBR_NONE, \ - jmp *%cs:pv_cpu_ops+PV_CPU_irq_enable_syscall_ret) + jmp PARA_INDIRECT(pv_cpu_ops+PV_CPU_irq_enable_syscall_ret)) #ifdef CONFIG_X86_32 -#define GET_CR0_INTO_EAX \ - push %ecx; push %edx; \ - call *pv_cpu_ops+PV_CPU_read_cr0; \ +#define GET_CR0_INTO_EAX \ + push %ecx; push %edx; \ + call PARA_INDIRECT(pv_cpu_ops+PV_CPU_read_cr0); \ pop %edx; pop %ecx #else #define SWAPGS \ PARA_SITE(PARA_PATCH(pv_cpu_ops, PV_CPU_swapgs), CLBR_NONE, \ PV_SAVE_REGS; \ - call *pv_cpu_ops+PV_CPU_swapgs; \ + call PARA_INDIRECT(pv_cpu_ops+PV_CPU_swapgs); \ PV_RESTORE_REGS \ ) -#define GET_CR2_INTO_RCX \ - call *pv_mmu_ops+PV_MMU_read_cr2; \ - movq %rax, %rcx; \ +#define GET_CR2_INTO_RCX \ + call PARA_INDIRECT(pv_mmu_ops+PV_MMU_read_cr2); \ + movq %rax, %rcx; \ xorq %rax, %rax; #endif -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/