There are several points of improvements:
1) Make kvmppc_free_hpt() check if allocation is made before attempt
to release. This follows kfree(p) semantics where p == NULL.
2) Return initialized @info parameter from kvmppc_allocate_hpt()
even if allocation fails.
This allows to use kvmppc_free_hpt() in the caller without
checking that preceded kvmppc_allocate_hpt() was successful
p = kmalloc(size, gfp);
kfree(p);
which is correct for both p != NULL and p == NULL. Followup
change will rely on this behaviour.
3) Better code reuse: kvmppc_free_hpt() can be reused on error
path in kvmppc_allocate_hpt() to avoid code duplication.
4) No need to check for !hpt if allocated from CMA: neither
pfn_to_kaddr() nor page_to_pfn() is 0 in case of page != NULL.
Signed-off-by: Serhii Popovych <[email protected]>
---
arch/powerpc/kvm/book3s_64_mmu_hv.c | 54 ++++++++++++++++++-------------------
1 file changed, 26 insertions(+), 28 deletions(-)
diff --git a/arch/powerpc/kvm/book3s_64_mmu_hv.c
b/arch/powerpc/kvm/book3s_64_mmu_hv.c
index 0534aab..3e9abd9 100644
--- a/arch/powerpc/kvm/book3s_64_mmu_hv.c
+++ b/arch/powerpc/kvm/book3s_64_mmu_hv.c
@@ -82,47 +82,44 @@ struct kvm_resize_hpt {
int kvmppc_allocate_hpt(struct kvm_hpt_info *info, u32 order)
{
unsigned long hpt = 0;
- int cma = 0;
- struct page *page = NULL;
- struct revmap_entry *rev;
+ int err, cma = 0;
+ struct page *page;
+ struct revmap_entry *rev = NULL;
unsigned long npte;
+ err = -EINVAL;
if ((order < PPC_MIN_HPT_ORDER) || (order > PPC_MAX_HPT_ORDER))
- return -EINVAL;
+ goto out;
+ err = -ENOMEM;
page = kvm_alloc_hpt_cma(1ul << (order - PAGE_SHIFT));
if (page) {
hpt = (unsigned long)pfn_to_kaddr(page_to_pfn(page));
memset((void *)hpt, 0, (1ul << order));
cma = 1;
- }
-
- if (!hpt)
+ } else {
hpt = __get_free_pages(GFP_KERNEL|__GFP_ZERO|__GFP_RETRY_MAYFAIL
|__GFP_NOWARN, order - PAGE_SHIFT);
-
- if (!hpt)
- return -ENOMEM;
+ if (!hpt)
+ goto out;
+ }
/* HPTEs are 2**4 bytes long */
npte = 1ul << (order - 4);
/* Allocate reverse map array */
- rev = vmalloc(sizeof(struct revmap_entry) * npte);
- if (!rev) {
- if (cma)
- kvm_free_hpt_cma(page, 1 << (order - PAGE_SHIFT));
- else
- free_pages(hpt, order - PAGE_SHIFT);
- return -ENOMEM;
- }
-
+ rev = vmalloc(sizeof(*rev) * npte);
+ if (rev)
+ err = 0;
+out:
info->order = order;
info->virt = hpt;
info->cma = cma;
info->rev = rev;
- return 0;
+ if (err)
+ kvmppc_free_hpt(info);
+ return err;
}
void kvmppc_set_hpt(struct kvm *kvm, struct kvm_hpt_info *info)
@@ -190,12 +187,14 @@ void kvmppc_free_hpt(struct kvm_hpt_info *info)
{
vfree(info->rev);
info->rev = NULL;
- if (info->cma)
- kvm_free_hpt_cma(virt_to_page(info->virt),
- 1 << (info->order - PAGE_SHIFT));
- else if (info->virt)
- free_pages(info->virt, info->order - PAGE_SHIFT);
- info->virt = 0;
+ if (info->virt) {
+ if (info->cma)
+ kvm_free_hpt_cma(virt_to_page(info->virt),
+ 1 << (info->order - PAGE_SHIFT));
+ else
+ free_pages(info->virt, info->order - PAGE_SHIFT);
+ info->virt = 0;
+ }
info->order = 0;
}
@@ -1423,8 +1422,7 @@ static void resize_hpt_release(struct kvm *kvm, struct
kvm_resize_hpt *resize)
if (!resize)
return;
- if (resize->hpt.virt)
- kvmppc_free_hpt(&resize->hpt);
+ kvmppc_free_hpt(&resize->hpt);
kvm->arch.resize_hpt = NULL;
kfree(resize);
--
1.8.3.1
