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KVM: arm64: Adjust partial code of hyp stage-1 map and guest stage-2 map

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Procedures of hyp stage-1 map and guest stage-2 map are quite different,
but they are tied closely by function kvm_set_valid_leaf_pte().
So adjust the relative code for ease of code maintenance in the future.

Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Yanan Wang <wangyanan55@huawei.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20210114121350.123684-2-wangyanan55@huawei.com
This commit is contained in:
Yanan Wang 2021-01-14 20:13:48 +08:00 committed by Marc Zyngier
parent 19c329f680
commit 8ed80051c8
1 changed files with 28 additions and 27 deletions
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55
arch/arm64/kvm/hyp/pgtable.c
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@ -170,10 +170,9 @@ static void kvm_set_table_pte(kvm_pte_t *ptep, kvm_pte_t *childp)
smp_store_release(ptep, pte);
}
static bool kvm_set_valid_leaf_pte(kvm_pte_t *ptep, u64 pa, kvm_pte_t attr,
u32 level)
static kvm_pte_t kvm_init_valid_leaf_pte(u64 pa, kvm_pte_t attr, u32 level)
{
kvm_pte_t old = *ptep, pte = kvm_phys_to_pte(pa);
kvm_pte_t pte = kvm_phys_to_pte(pa);
u64 type = (level == KVM_PGTABLE_MAX_LEVELS - 1) ? KVM_PTE_TYPE_PAGE :
KVM_PTE_TYPE_BLOCK;
@ -181,12 +180,7 @@ static bool kvm_set_valid_leaf_pte(kvm_pte_t *ptep, u64 pa, kvm_pte_t attr,
pte |= FIELD_PREP(KVM_PTE_TYPE, type);
pte |= KVM_PTE_VALID;
/* Tolerate KVM recreating the exact same mapping. */
if (kvm_pte_valid(old))
return old == pte;
smp_store_release(ptep, pte);
return true;
return pte;
}
static int kvm_pgtable_visitor_cb(struct kvm_pgtable_walk_data *data, u64 addr,
@ -341,12 +335,17 @@ static int hyp_map_set_prot_attr(enum kvm_pgtable_prot prot,
static bool hyp_map_walker_try_leaf(u64 addr, u64 end, u32 level,
kvm_pte_t *ptep, struct hyp_map_data *data)
{
kvm_pte_t new, old = *ptep;
u64 granule = kvm_granule_size(level), phys = data->phys;
if (!kvm_block_mapping_supported(addr, end, phys, level))
return false;
WARN_ON(!kvm_set_valid_leaf_pte(ptep, phys, data->attr, level));
/* Tolerate KVM recreating the exact same mapping */
new = kvm_init_valid_leaf_pte(phys, data->attr, level);
if (old != new && !WARN_ON(kvm_pte_valid(old)))
smp_store_release(ptep, new);
data->phys += granule;
return true;
}
@ -465,27 +464,30 @@ static bool stage2_map_walker_try_leaf(u64 addr, u64 end, u32 level,
kvm_pte_t *ptep,
struct stage2_map_data *data)
{
kvm_pte_t new, old = *ptep;
u64 granule = kvm_granule_size(level), phys = data->phys;
struct page *page = virt_to_page(ptep);
if (!kvm_block_mapping_supported(addr, end, phys, level))
return false;
/*
* If the PTE was already valid, drop the refcount on the table
* early, as it will be bumped-up again in stage2_map_walk_leaf().
* This ensures that the refcount stays constant across a valid to
* valid PTE update.
*/
if (kvm_pte_valid(*ptep))
put_page(virt_to_page(ptep));
new = kvm_init_valid_leaf_pte(phys, data->attr, level);
if (kvm_pte_valid(old)) {
/* Tolerate KVM recreating the exact same mapping */
if (old == new)
goto out;
if (kvm_set_valid_leaf_pte(ptep, phys, data->attr, level))
goto out;
/*
* There's an existing different valid leaf entry, so perform
* break-before-make.
*/
kvm_set_invalid_pte(ptep);
kvm_call_hyp(__kvm_tlb_flush_vmid_ipa, data->mmu, addr, level);
put_page(page);
}
/* There's an existing valid leaf entry, so perform break-before-make */
kvm_set_invalid_pte(ptep);
kvm_call_hyp(__kvm_tlb_flush_vmid_ipa, data->mmu, addr, level);
kvm_set_valid_leaf_pte(ptep, phys, data->attr, level);
smp_store_release(ptep, new);
get_page(page);
out:
data->phys += granule;
return true;
@ -527,7 +529,7 @@ static int stage2_map_walk_leaf(u64 addr, u64 end, u32 level, kvm_pte_t *ptep,
}
if (stage2_map_walker_try_leaf(addr, end, level, ptep, data))
goto out_get_page;
return 0;
if (WARN_ON(level == KVM_PGTABLE_MAX_LEVELS - 1))
return -EINVAL;
@ -551,9 +553,8 @@ static int stage2_map_walk_leaf(u64 addr, u64 end, u32 level, kvm_pte_t *ptep,
}
kvm_set_table_pte(ptep, childp);
out_get_page:
get_page(page);
return 0;
}