KVM: MMU: Convert the paging mode shadow walk to use the generic walker

Signed-off-by: Avi Kivity <avi@qumranet.com>
This commit is contained in:
Avi Kivity 2008-08-22 19:11:39 +03:00
parent 140754bc80
commit abb9e0b8e3

View File

@ -25,6 +25,7 @@
#if PTTYPE == 64
#define pt_element_t u64
#define guest_walker guest_walker64
#define shadow_walker shadow_walker64
#define FNAME(name) paging##64_##name
#define PT_BASE_ADDR_MASK PT64_BASE_ADDR_MASK
#define PT_DIR_BASE_ADDR_MASK PT64_DIR_BASE_ADDR_MASK
@ -41,6 +42,7 @@
#elif PTTYPE == 32
#define pt_element_t u32
#define guest_walker guest_walker32
#define shadow_walker shadow_walker32
#define FNAME(name) paging##32_##name
#define PT_BASE_ADDR_MASK PT32_BASE_ADDR_MASK
#define PT_DIR_BASE_ADDR_MASK PT32_DIR_BASE_ADDR_MASK
@ -71,6 +73,17 @@ struct guest_walker {
u32 error_code;
};
struct shadow_walker {
struct kvm_shadow_walk walker;
struct guest_walker *guest_walker;
int user_fault;
int write_fault;
int largepage;
int *ptwrite;
pfn_t pfn;
u64 *sptep;
};
static gfn_t gpte_to_gfn(pt_element_t gpte)
{
return (gpte & PT_BASE_ADDR_MASK) >> PAGE_SHIFT;
@ -272,86 +285,86 @@ static void FNAME(update_pte)(struct kvm_vcpu *vcpu, struct kvm_mmu_page *page,
/*
* Fetch a shadow pte for a specific level in the paging hierarchy.
*/
static int FNAME(shadow_walk_entry)(struct kvm_shadow_walk *_sw,
struct kvm_vcpu *vcpu, gva_t addr,
u64 *sptep, int level)
{
struct shadow_walker *sw =
container_of(_sw, struct shadow_walker, walker);
struct guest_walker *gw = sw->guest_walker;
unsigned access = gw->pt_access;
struct kvm_mmu_page *shadow_page;
u64 spte;
int metaphysical;
gfn_t table_gfn;
int r;
pt_element_t curr_pte;
if (level == PT_PAGE_TABLE_LEVEL
|| (sw->largepage && level == PT_DIRECTORY_LEVEL)) {
mmu_set_spte(vcpu, sptep, access, gw->pte_access & access,
sw->user_fault, sw->write_fault,
gw->ptes[gw->level-1] & PT_DIRTY_MASK,
sw->ptwrite, sw->largepage, gw->gfn, sw->pfn,
false);
sw->sptep = sptep;
return 1;
}
if (is_shadow_present_pte(*sptep) && !is_large_pte(*sptep))
return 0;
if (is_large_pte(*sptep))
rmap_remove(vcpu->kvm, sptep);
if (level == PT_DIRECTORY_LEVEL && gw->level == PT_DIRECTORY_LEVEL) {
metaphysical = 1;
if (!is_dirty_pte(gw->ptes[level - 1]))
access &= ~ACC_WRITE_MASK;
table_gfn = gpte_to_gfn(gw->ptes[level - 1]);
} else {
metaphysical = 0;
table_gfn = gw->table_gfn[level - 2];
}
shadow_page = kvm_mmu_get_page(vcpu, table_gfn, addr, level-1,
metaphysical, access, sptep);
if (!metaphysical) {
r = kvm_read_guest_atomic(vcpu->kvm, gw->pte_gpa[level - 2],
&curr_pte, sizeof(curr_pte));
if (r || curr_pte != gw->ptes[level - 2]) {
kvm_release_pfn_clean(sw->pfn);
sw->sptep = NULL;
return 1;
}
}
spte = __pa(shadow_page->spt) | PT_PRESENT_MASK | PT_ACCESSED_MASK
| PT_WRITABLE_MASK | PT_USER_MASK;
*sptep = spte;
return 0;
}
static u64 *FNAME(fetch)(struct kvm_vcpu *vcpu, gva_t addr,
struct guest_walker *walker,
struct guest_walker *guest_walker,
int user_fault, int write_fault, int largepage,
int *ptwrite, pfn_t pfn)
{
hpa_t shadow_addr;
int level;
u64 *shadow_ent;
unsigned access = walker->pt_access;
struct shadow_walker walker = {
.walker = { .entry = FNAME(shadow_walk_entry), },
.guest_walker = guest_walker,
.user_fault = user_fault,
.write_fault = write_fault,
.largepage = largepage,
.ptwrite = ptwrite,
.pfn = pfn,
};
if (!is_present_pte(walker->ptes[walker->level - 1]))
if (!is_present_pte(guest_walker->ptes[guest_walker->level - 1]))
return NULL;
shadow_addr = vcpu->arch.mmu.root_hpa;
level = vcpu->arch.mmu.shadow_root_level;
if (level == PT32E_ROOT_LEVEL) {
shadow_addr = vcpu->arch.mmu.pae_root[(addr >> 30) & 3];
shadow_addr &= PT64_BASE_ADDR_MASK;
--level;
}
walk_shadow(&walker.walker, vcpu, addr);
for (; ; level--) {
u32 index = SHADOW_PT_INDEX(addr, level);
struct kvm_mmu_page *shadow_page;
u64 shadow_pte;
int metaphysical;
gfn_t table_gfn;
shadow_ent = ((u64 *)__va(shadow_addr)) + index;
if (level == PT_PAGE_TABLE_LEVEL)
break;
if (largepage && level == PT_DIRECTORY_LEVEL)
break;
if (is_shadow_present_pte(*shadow_ent)
&& !is_large_pte(*shadow_ent)) {
shadow_addr = *shadow_ent & PT64_BASE_ADDR_MASK;
continue;
}
if (is_large_pte(*shadow_ent))
rmap_remove(vcpu->kvm, shadow_ent);
if (level - 1 == PT_PAGE_TABLE_LEVEL
&& walker->level == PT_DIRECTORY_LEVEL) {
metaphysical = 1;
if (!is_dirty_pte(walker->ptes[level - 1]))
access &= ~ACC_WRITE_MASK;
table_gfn = gpte_to_gfn(walker->ptes[level - 1]);
} else {
metaphysical = 0;
table_gfn = walker->table_gfn[level - 2];
}
shadow_page = kvm_mmu_get_page(vcpu, table_gfn, addr, level-1,
metaphysical, access,
shadow_ent);
if (!metaphysical) {
int r;
pt_element_t curr_pte;
r = kvm_read_guest_atomic(vcpu->kvm,
walker->pte_gpa[level - 2],
&curr_pte, sizeof(curr_pte));
if (r || curr_pte != walker->ptes[level - 2]) {
kvm_release_pfn_clean(pfn);
return NULL;
}
}
shadow_addr = __pa(shadow_page->spt);
shadow_pte = shadow_addr | PT_PRESENT_MASK | PT_ACCESSED_MASK
| PT_WRITABLE_MASK | PT_USER_MASK;
set_shadow_pte(shadow_ent, shadow_pte);
}
mmu_set_spte(vcpu, shadow_ent, access, walker->pte_access & access,
user_fault, write_fault,
walker->ptes[walker->level-1] & PT_DIRTY_MASK,
ptwrite, largepage, walker->gfn, pfn, false);
return shadow_ent;
return walker.sptep;
}
/*
@ -499,6 +512,7 @@ static void FNAME(prefetch_page)(struct kvm_vcpu *vcpu,
#undef pt_element_t
#undef guest_walker
#undef shadow_walker
#undef FNAME
#undef PT_BASE_ADDR_MASK
#undef PT_INDEX