diff options
Diffstat (limited to 'arch/i386/xen/enlighten.c')
| -rw-r--r-- | arch/i386/xen/enlighten.c | 107 |
1 files changed, 54 insertions, 53 deletions
diff --git a/arch/i386/xen/enlighten.c b/arch/i386/xen/enlighten.c index e33fa0990ed..4fa62a4cb7c 100644 --- a/arch/i386/xen/enlighten.c +++ b/arch/i386/xen/enlighten.c @@ -115,6 +115,7 @@ static void __init xen_vcpu_setup(int cpu) /* This cpu is using the registered vcpu info, even if later ones fail to. */ per_cpu(xen_vcpu, cpu) = vcpup; + printk(KERN_DEBUG "cpu %d using vcpu_info at %p\n", cpu, vcpup); } @@ -177,20 +178,6 @@ static unsigned long xen_save_fl(void) return (-flags) & X86_EFLAGS_IF; } -static unsigned long xen_save_fl_direct(void) -{ - unsigned long flags; - - /* flag has opposite sense of mask */ - flags = !x86_read_percpu(xen_vcpu_info.evtchn_upcall_mask); - - /* convert to IF type flag - -0 -> 0x00000000 - -1 -> 0xffffffff - */ - return (-flags) & X86_EFLAGS_IF; -} - static void xen_restore_fl(unsigned long flags) { struct vcpu_info *vcpu; @@ -217,25 +204,6 @@ static void xen_restore_fl(unsigned long flags) } } -static void xen_restore_fl_direct(unsigned long flags) -{ - /* convert from IF type flag */ - flags = !(flags & X86_EFLAGS_IF); - - /* This is an atomic update, so no need to worry about - preemption. */ - x86_write_percpu(xen_vcpu_info.evtchn_upcall_mask, flags); - - /* If we get preempted here, then any pending event will be - handled anyway. */ - - if (flags == 0) { - barrier(); /* unmask then check (avoid races) */ - if (unlikely(x86_read_percpu(xen_vcpu_info.evtchn_upcall_pending))) - force_evtchn_callback(); - } -} - static void xen_irq_disable(void) { /* There's a one instruction preempt window here. We need to @@ -246,12 +214,6 @@ static void xen_irq_disable(void) preempt_enable_no_resched(); } -static void xen_irq_disable_direct(void) -{ - /* Atomic update, so preemption not a concern. */ - x86_write_percpu(xen_vcpu_info.evtchn_upcall_mask, 1); -} - static void xen_irq_enable(void) { struct vcpu_info *vcpu; @@ -272,19 +234,6 @@ static void xen_irq_enable(void) force_evtchn_callback(); } -static void xen_irq_enable_direct(void) -{ - /* Atomic update, so preemption not a concern. */ - x86_write_percpu(xen_vcpu_info.evtchn_upcall_mask, 0); - - /* Doesn't matter if we get preempted here, because any - pending event will get dealt with anyway. */ - - barrier(); /* unmask then check (avoid races) */ - if (unlikely(x86_read_percpu(xen_vcpu_info.evtchn_upcall_pending))) - force_evtchn_callback(); -} - static void xen_safe_halt(void) { /* Blocking includes an implicit local_irq_enable(). */ @@ -892,6 +841,57 @@ void __init xen_setup_vcpu_info_placement(void) } } +static unsigned xen_patch(u8 type, u16 clobbers, void *insns, unsigned len) +{ + char *start, *end, *reloc; + unsigned ret; + + start = end = reloc = NULL; + +#define SITE(x) \ + case PARAVIRT_PATCH(x): \ + if (have_vcpu_info_placement) { \ + start = (char *)xen_##x##_direct; \ + end = xen_##x##_direct_end; \ + reloc = xen_##x##_direct_reloc; \ + } \ + goto patch_site + + switch (type) { + SITE(irq_enable); + SITE(irq_disable); + SITE(save_fl); + SITE(restore_fl); +#undef SITE + + patch_site: + if (start == NULL || (end-start) > len) + goto default_patch; + + ret = paravirt_patch_insns(insns, len, start, end); + + /* Note: because reloc is assigned from something that + appears to be an array, gcc assumes it's non-null, + but doesn't know its relationship with start and + end. */ + if (reloc > start && reloc < end) { + int reloc_off = reloc - start; + long *relocp = (long *)(insns + reloc_off); + long delta = start - (char *)insns; + + *relocp += delta; + } + break; + + default_patch: + default: + ret = paravirt_patch_default(type, clobbers, insns, len); + break; + } + + return ret; +} + static const struct paravirt_ops xen_paravirt_ops __initdata = { .paravirt_enabled = 1, .shared_kernel_pmd = 0, @@ -899,7 +899,7 @@ static const struct paravirt_ops xen_paravirt_ops __initdata = { .name = "Xen", .banner = xen_banner, - .patch = paravirt_patch_default, + .patch = xen_patch, .memory_setup = xen_memory_setup, .arch_setup = xen_arch_setup, @@ -1076,6 +1076,7 @@ static const struct machine_ops __initdata xen_machine_ops = { .emergency_restart = xen_emergency_restart, }; + /* First C function to be called on Xen boot */ asmlinkage void __init xen_start_kernel(void) { |