[PATCH 16/64] virt: use mm locking wrappers

From: Davidlohr Bueso
Date: Sun Feb 04 2018 - 20:42:22 EST


From: Davidlohr Bueso <dave@xxxxxxxxxxxx>

No change in semantics.

Signed-off-by: Davidlohr Bueso <dbueso@xxxxxxx>
---
virt/kvm/arm/mmu.c | 17 ++++++++++-------
virt/kvm/async_pf.c | 4 ++--
virt/kvm/kvm_main.c | 9 +++++----
3 files changed, 17 insertions(+), 13 deletions(-)

diff --git a/virt/kvm/arm/mmu.c b/virt/kvm/arm/mmu.c
index ec62d1cccab7..9a866a639c2c 100644
--- a/virt/kvm/arm/mmu.c
+++ b/virt/kvm/arm/mmu.c
@@ -815,9 +815,10 @@ void stage2_unmap_vm(struct kvm *kvm)
struct kvm_memslots *slots;
struct kvm_memory_slot *memslot;
int idx;
+ DEFINE_RANGE_LOCK_FULL(mmrange);

idx = srcu_read_lock(&kvm->srcu);
- down_read(&current->mm->mmap_sem);
+ mm_read_lock(current->mm, &mmrange);
spin_lock(&kvm->mmu_lock);

slots = kvm_memslots(kvm);
@@ -825,7 +826,7 @@ void stage2_unmap_vm(struct kvm *kvm)
stage2_unmap_memslot(kvm, memslot);

spin_unlock(&kvm->mmu_lock);
- up_read(&current->mm->mmap_sem);
+ mm_read_unlock(current->mm, &mmrange);
srcu_read_unlock(&kvm->srcu, idx);
}

@@ -1317,6 +1318,7 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
pgprot_t mem_type = PAGE_S2;
bool logging_active = memslot_is_logging(memslot);
unsigned long flags = 0;
+ DEFINE_RANGE_LOCK_FULL(mmrange);

write_fault = kvm_is_write_fault(vcpu);
exec_fault = kvm_vcpu_trap_is_iabt(vcpu);
@@ -1328,11 +1330,11 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
}

/* Let's check if we will get back a huge page backed by hugetlbfs */
- down_read(&current->mm->mmap_sem);
+ mm_read_lock(current->mm, &mmrange);
vma = find_vma_intersection(current->mm, hva, hva + 1);
if (unlikely(!vma)) {
kvm_err("Failed to find VMA for hva 0x%lx\n", hva);
- up_read(&current->mm->mmap_sem);
+ mm_read_unlock(current->mm, &mmrange);
return -EFAULT;
}

@@ -1353,7 +1355,7 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
((memslot->base_gfn << PAGE_SHIFT) & ~PMD_MASK))
force_pte = true;
}
- up_read(&current->mm->mmap_sem);
+ mm_read_unlock(current->mm, &mmrange);

/* We need minimum second+third level pages */
ret = mmu_topup_memory_cache(memcache, KVM_MMU_CACHE_MIN_PAGES,
@@ -1889,6 +1891,7 @@ int kvm_arch_prepare_memory_region(struct kvm *kvm,
hva_t reg_end = hva + mem->memory_size;
bool writable = !(mem->flags & KVM_MEM_READONLY);
int ret = 0;
+ DEFINE_RANGE_LOCK_FULL(mmrange);

if (change != KVM_MR_CREATE && change != KVM_MR_MOVE &&
change != KVM_MR_FLAGS_ONLY)
@@ -1902,7 +1905,7 @@ int kvm_arch_prepare_memory_region(struct kvm *kvm,
(KVM_PHYS_SIZE >> PAGE_SHIFT))
return -EFAULT;

- down_read(&current->mm->mmap_sem);
+ mm_read_lock(current->mm, &mmrange);
/*
* A memory region could potentially cover multiple VMAs, and any holes
* between them, so iterate over all of them to find out if we can map
@@ -1970,7 +1973,7 @@ int kvm_arch_prepare_memory_region(struct kvm *kvm,
stage2_flush_memslot(kvm, memslot);
spin_unlock(&kvm->mmu_lock);
out:
- up_read(&current->mm->mmap_sem);
+ mm_read_unlock(current->mm, &mmrange);
return ret;
}

diff --git a/virt/kvm/async_pf.c b/virt/kvm/async_pf.c
index 4cd2b93bb20c..ed559789d7cb 100644
--- a/virt/kvm/async_pf.c
+++ b/virt/kvm/async_pf.c
@@ -87,11 +87,11 @@ static void async_pf_execute(struct work_struct *work)
* mm and might be done in another context, so we must
* access remotely.
*/
- down_read(&mm->mmap_sem);
+ mm_read_lock(mm, &mmrange);
get_user_pages_remote(NULL, mm, addr, 1, FOLL_WRITE, NULL, NULL,
&locked, &mmrange);
if (locked)
- up_read(&mm->mmap_sem);
+ mm_read_unlock(mm, &mmrange);

kvm_async_page_present_sync(vcpu, apf);

diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 86ec078f4c3b..92fd944e7e3a 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -1222,6 +1222,7 @@ EXPORT_SYMBOL_GPL(kvm_is_visible_gfn);
unsigned long kvm_host_page_size(struct kvm *kvm, gfn_t gfn)
{
struct vm_area_struct *vma;
+ DEFINE_RANGE_LOCK_FULL(mmrange);
unsigned long addr, size;

size = PAGE_SIZE;
@@ -1230,7 +1231,7 @@ unsigned long kvm_host_page_size(struct kvm *kvm, gfn_t gfn)
if (kvm_is_error_hva(addr))
return PAGE_SIZE;

- down_read(&current->mm->mmap_sem);
+ mm_read_lock(current->mm, &mmrange);
vma = find_vma(current->mm, addr);
if (!vma)
goto out;
@@ -1238,7 +1239,7 @@ unsigned long kvm_host_page_size(struct kvm *kvm, gfn_t gfn)
size = vma_kernel_pagesize(vma);

out:
- up_read(&current->mm->mmap_sem);
+ mm_read_unlock(current->mm, &mmrange);

return size;
}
@@ -1494,7 +1495,7 @@ static kvm_pfn_t hva_to_pfn(unsigned long addr, bool atomic, bool *async,
if (npages == 1)
return pfn;

- down_read(&current->mm->mmap_sem);
+ mm_read_lock(current->mm, &mmrange);
if (npages == -EHWPOISON ||
(!async && check_user_page_hwpoison(addr, &mmrange))) {
pfn = KVM_PFN_ERR_HWPOISON;
@@ -1519,7 +1520,7 @@ static kvm_pfn_t hva_to_pfn(unsigned long addr, bool atomic, bool *async,
pfn = KVM_PFN_ERR_FAULT;
}
exit:
- up_read(&current->mm->mmap_sem);
+ mm_read_unlock(current->mm, &mmrange);
return pfn;
}

--
2.13.6