FROMLIST: KVM: arm64: Avoid free_page() in page-table allocator

Currently, the KVM page-table allocator uses a mix of put_page() and
free_page() calls depending on the context even though page-allocation
is always achieved using variants of __get_free_page().

Make the code consistent by using put_page() throughout, and reduce the
memory management API surface used by the page-table code. This will
ease factoring out page-allocation from pgtable.c, which is a
pre-requisite to creating page-tables at EL2.

Acked-by: Will Deacon <will@kernel.org>
Signed-off-by: Quentin Perret <qperret@google.com>
Link: https://lore.kernel.org/r/20210315143536.214621-6-qperret@google.com
Bug: 178098380
Change-Id: I998e88dd31decc7dd1141af9dbda5e60c8370baa
This commit is contained in:
Quentin Perret
2021-03-15 14:35:05 +00:00
parent c758e8e4b1
commit 620bb5f9c9

View File

@@ -414,7 +414,7 @@ int kvm_pgtable_hyp_init(struct kvm_pgtable *pgt, u32 va_bits)
static int hyp_free_walker(u64 addr, u64 end, u32 level, kvm_pte_t *ptep,
enum kvm_pgtable_walk_flags flag, void * const arg)
{
free_page((unsigned long)kvm_pte_follow(*ptep));
put_page(virt_to_page(kvm_pte_follow(*ptep)));
return 0;
}
@@ -426,7 +426,7 @@ void kvm_pgtable_hyp_destroy(struct kvm_pgtable *pgt)
};
WARN_ON(kvm_pgtable_walk(pgt, 0, BIT(pgt->ia_bits), &walker));
free_page((unsigned long)pgt->pgd);
put_page(virt_to_page(pgt->pgd));
pgt->pgd = NULL;
}
@@ -578,7 +578,7 @@ static int stage2_map_walk_table_post(u64 addr, u64 end, u32 level,
if (!data->anchor)
return 0;
free_page((unsigned long)kvm_pte_follow(*ptep));
put_page(virt_to_page(kvm_pte_follow(*ptep)));
put_page(virt_to_page(ptep));
if (data->anchor == ptep) {
@@ -701,7 +701,7 @@ static int stage2_unmap_walker(u64 addr, u64 end, u32 level, kvm_pte_t *ptep,
}
if (childp)
free_page((unsigned long)childp);
put_page(virt_to_page(childp));
return 0;
}
@@ -898,7 +898,7 @@ static int stage2_free_walker(u64 addr, u64 end, u32 level, kvm_pte_t *ptep,
put_page(virt_to_page(ptep));
if (kvm_pte_table(pte, level))
free_page((unsigned long)kvm_pte_follow(pte));
put_page(virt_to_page(kvm_pte_follow(pte)));
return 0;
}