From a11b6c53f6f178978f67a906a54ed6952cd6f048 Mon Sep 17 00:00:00 2001 From: Keir Fraser Date: Sat, 18 Sep 2010 08:57:15 +0100 Subject: [PATCH] x86_32: [un]map_domain_page() is now IRQ safe. Signed-off-by: Keir Fraser --- xen/arch/x86/x86_32/domain_page.c | 21 ++++++++++++--------- 1 file changed, 12 insertions(+), 9 deletions(-) diff --git a/xen/arch/x86/x86_32/domain_page.c b/xen/arch/x86/x86_32/domain_page.c index 6d09a879b3..55a3380776 100644 --- a/xen/arch/x86/x86_32/domain_page.c +++ b/xen/arch/x86/x86_32/domain_page.c @@ -43,15 +43,13 @@ static inline struct vcpu *mapcache_current_vcpu(void) void *map_domain_page(unsigned long mfn) { - unsigned long va; - unsigned int idx, i, flags; + unsigned long va, flags; + unsigned int idx, i; struct vcpu *v; struct mapcache_domain *dcache; struct mapcache_vcpu *vcache; struct vcpu_maphash_entry *hashent; - ASSERT(!in_irq()); - perfc_incr(map_domain_page_count); v = mapcache_current_vcpu(); @@ -59,6 +57,8 @@ void *map_domain_page(unsigned long mfn) dcache = &v->domain->arch.mapcache; vcache = &v->arch.mapcache; + local_irq_save(flags); + hashent = &vcache->hash[MAPHASH_HASHFN(mfn)]; if ( hashent->mfn == mfn ) { @@ -70,7 +70,7 @@ void *map_domain_page(unsigned long mfn) goto out; } - spin_lock_irqsave(&dcache->lock, flags); + spin_lock(&dcache->lock); /* Has some other CPU caused a wrap? We must flush if so. */ if ( unlikely(dcache->epoch != vcache->shadow_epoch) ) @@ -106,11 +106,12 @@ void *map_domain_page(unsigned long mfn) set_bit(idx, dcache->inuse); dcache->cursor = idx + 1; - spin_unlock_irqrestore(&dcache->lock, flags); + spin_unlock(&dcache->lock); l1e_write(&dcache->l1tab[idx], l1e_from_pfn(mfn, __PAGE_HYPERVISOR)); out: + local_irq_restore(flags); va = MAPCACHE_VIRT_START + (idx << PAGE_SHIFT); return (void *)va; } @@ -120,11 +121,9 @@ void unmap_domain_page(const void *va) unsigned int idx; struct vcpu *v; struct mapcache_domain *dcache; - unsigned long mfn; + unsigned long mfn, flags; struct vcpu_maphash_entry *hashent; - ASSERT(!in_irq()); - ASSERT((void *)MAPCACHE_VIRT_START <= va); ASSERT(va < (void *)MAPCACHE_VIRT_END); @@ -136,6 +135,8 @@ void unmap_domain_page(const void *va) mfn = l1e_get_pfn(dcache->l1tab[idx]); hashent = &v->arch.mapcache.hash[MAPHASH_HASHFN(mfn)]; + local_irq_save(flags); + if ( hashent->idx == idx ) { ASSERT(hashent->mfn == mfn); @@ -164,6 +165,8 @@ void unmap_domain_page(const void *va) /* /Second/, mark as garbage. */ set_bit(idx, dcache->garbage); } + + local_irq_restore(flags); } void mapcache_domain_init(struct domain *d) -- 2.30.2