Abstract the operation of rmap, then we can use it for the reverse mapping of parent pte in the later patch
Signed-off-by: Xiao Guangrong <[email protected]> --- arch/x86/kvm/mmu.c | 142 +++++++++++++++++++++++++++++----------------------- 1 files changed, 79 insertions(+), 63 deletions(-) diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index 971e2d2..8da77b3 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -590,28 +590,9 @@ static int mapping_level(struct kvm_vcpu *vcpu, gfn_t large_gfn) } /* - * Take gfn and return the reverse mapping to it. - */ - -static unsigned long *gfn_to_rmap(struct kvm *kvm, gfn_t gfn, int level) -{ - struct kvm_memory_slot *slot; - struct kvm_lpage_info *linfo; - - slot = gfn_to_memslot(kvm, gfn); - if (likely(level == PT_PAGE_TABLE_LEVEL)) - return &slot->rmap[gfn - slot->base_gfn]; - - linfo = lpage_info_slot(gfn, slot, level); - - return &linfo->rmap_pde; -} - -/* * Reverse mapping data structures: * - * If rmapp bit zero is zero, then rmapp point to the shadw page table entry - * that points to page_address(page). + * If rmapp bit zero is zero, then rmapp point to the spte. * * If rmapp bit zero is one, (then rmap & ~1) points to a struct kvm_rmap_desc * containing more mappings. @@ -620,18 +601,11 @@ static unsigned long *gfn_to_rmap(struct kvm *kvm, gfn_t gfn, int level) * the spte was not added. * */ -static int rmap_add(struct kvm_vcpu *vcpu, u64 *spte, gfn_t gfn) +static int __rmap_add(struct kvm_vcpu *vcpu, u64 *spte, unsigned long *rmapp) { - struct kvm_mmu_page *sp; struct kvm_rmap_desc *desc; - unsigned long *rmapp; int i, count = 0; - if (!is_rmap_spte(*spte)) - return count; - sp = page_header(__pa(spte)); - kvm_mmu_page_set_gfn(sp, spte - sp->spt, gfn); - rmapp = gfn_to_rmap(vcpu->kvm, gfn, sp->role.level); if (!*rmapp) { rmap_printk("rmap_add: %p %llx 0->1\n", spte, *spte); *rmapp = (unsigned long)spte; @@ -660,7 +634,33 @@ static int rmap_add(struct kvm_vcpu *vcpu, u64 *spte, gfn_t gfn) return count; } -static void rmap_desc_remove_entry(unsigned long *rmapp, +static u64 *__rmap_next(unsigned long *rmapp, u64 *spte) +{ + struct kvm_rmap_desc *desc; + u64 *prev_spte; + int i; + + if (!*rmapp) + return NULL; + else if (!(*rmapp & 1)) { + if (!spte) + return (u64 *)*rmapp; + return NULL; + } + desc = (struct kvm_rmap_desc *)(*rmapp & ~1ul); + prev_spte = NULL; + while (desc) { + for (i = 0; i < RMAP_EXT && desc->sptes[i]; ++i) { + if (prev_spte == spte) + return desc->sptes[i]; + prev_spte = desc->sptes[i]; + } + desc = desc->more; + } + return NULL; +} + +static void __rmap_desc_remove_entry(unsigned long *rmapp, struct kvm_rmap_desc *desc, int i, struct kvm_rmap_desc *prev_desc) @@ -683,18 +683,12 @@ static void rmap_desc_remove_entry(unsigned long *rmapp, mmu_free_rmap_desc(desc); } -static void rmap_remove(struct kvm *kvm, u64 *spte) +static void __rmap_remove(u64 *spte, unsigned long *rmapp) { struct kvm_rmap_desc *desc; struct kvm_rmap_desc *prev_desc; - struct kvm_mmu_page *sp; - gfn_t gfn; - unsigned long *rmapp; int i; - sp = page_header(__pa(spte)); - gfn = kvm_mmu_page_get_gfn(sp, spte - sp->spt); - rmapp = gfn_to_rmap(kvm, gfn, sp->role.level); if (!*rmapp) { printk(KERN_ERR "rmap_remove: %p 0->BUG\n", spte); BUG(); @@ -712,7 +706,7 @@ static void rmap_remove(struct kvm *kvm, u64 *spte) while (desc) { for (i = 0; i < RMAP_EXT && desc->sptes[i]; ++i) if (desc->sptes[i] == spte) { - rmap_desc_remove_entry(rmapp, + __rmap_desc_remove_entry(rmapp, desc, i, prev_desc); return; @@ -725,6 +719,54 @@ static void rmap_remove(struct kvm *kvm, u64 *spte) } } +/* + * Take gfn and return the reverse mapping to it. + */ +static unsigned long *gfn_to_rmap(struct kvm *kvm, gfn_t gfn, int level) +{ + struct kvm_memory_slot *slot; + struct kvm_lpage_info *linfo; + + slot = gfn_to_memslot(kvm, gfn); + if (likely(level == PT_PAGE_TABLE_LEVEL)) + return &slot->rmap[gfn - slot->base_gfn]; + + linfo = lpage_info_slot(gfn, slot, level); + + return &linfo->rmap_pde; +} + +static int rmap_add(struct kvm_vcpu *vcpu, u64 *spte, gfn_t gfn) +{ + struct kvm_mmu_page *sp; + unsigned long *rmapp; + + if (!is_rmap_spte(*spte)) + return 0; + + sp = page_header(__pa(spte)); + kvm_mmu_page_set_gfn(sp, spte - sp->spt, gfn); + rmapp = gfn_to_rmap(vcpu->kvm, gfn, sp->role.level); + return __rmap_add(vcpu, spte, rmapp); +} + +static u64 *rmap_next(struct kvm *kvm, unsigned long *rmapp, u64 *spte) +{ + return __rmap_next(rmapp, spte); +} + +static void rmap_remove(struct kvm *kvm, u64 *spte) +{ + struct kvm_mmu_page *sp; + gfn_t gfn; + unsigned long *rmapp; + + sp = page_header(__pa(spte)); + gfn = kvm_mmu_page_get_gfn(sp, spte - sp->spt); + rmapp = gfn_to_rmap(kvm, gfn, sp->role.level); + __rmap_remove(spte, rmapp); +} + static int set_spte_track_bits(u64 *sptep, u64 new_spte) { pfn_t pfn; @@ -752,32 +794,6 @@ static void drop_spte(struct kvm *kvm, u64 *sptep, u64 new_spte) rmap_remove(kvm, sptep); } -static u64 *rmap_next(struct kvm *kvm, unsigned long *rmapp, u64 *spte) -{ - struct kvm_rmap_desc *desc; - u64 *prev_spte; - int i; - - if (!*rmapp) - return NULL; - else if (!(*rmapp & 1)) { - if (!spte) - return (u64 *)*rmapp; - return NULL; - } - desc = (struct kvm_rmap_desc *)(*rmapp & ~1ul); - prev_spte = NULL; - while (desc) { - for (i = 0; i < RMAP_EXT && desc->sptes[i]; ++i) { - if (prev_spte == spte) - return desc->sptes[i]; - prev_spte = desc->sptes[i]; - } - desc = desc->more; - } - return NULL; -} - static int rmap_write_protect(struct kvm *kvm, u64 gfn) { unsigned long *rmapp; -- 1.7.4.4 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
