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Subject[PATCH v2 1/2] KVM: PPC: Book3S HV: move kvmppc_svm_page_out up
Date
kvmppc_svm_page_out() will need to be called by kvmppc_uvmem_drop_pages()
so move it upper in this file.

Furthermore it will be interesting to call this function when already
holding the kvm->arch.uvmem_lock, so prefix the original function with __
and remove the locking in it, and introduce a wrapper which call that
function with the lock held.

There is no functional change.

Cc: Ram Pai <linuxram@us.ibm.com>
Cc: Bharata B Rao <bharata@linux.ibm.com>
Cc: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Laurent Dufour <ldufour@linux.ibm.com>
---
arch/powerpc/kvm/book3s_hv_uvmem.c | 166 ++++++++++++++++-------------
1 file changed, 90 insertions(+), 76 deletions(-)

diff --git a/arch/powerpc/kvm/book3s_hv_uvmem.c b/arch/powerpc/kvm/book3s_hv_uvmem.c
index a2b4d259f8b0..5a4b02d3f651 100644
--- a/arch/powerpc/kvm/book3s_hv_uvmem.c
+++ b/arch/powerpc/kvm/book3s_hv_uvmem.c
@@ -526,6 +526,96 @@ unsigned long kvmppc_h_svm_init_done(struct kvm *kvm)
return ret;
}

+/*
+ * Provision a new page on HV side and copy over the contents
+ * from secure memory using UV_PAGE_OUT uvcall.
+ * Caller must held kvm->arch.uvmem_lock.
+ */
+static int __kvmppc_svm_page_out(struct vm_area_struct *vma,
+ unsigned long start,
+ unsigned long end, unsigned long page_shift,
+ struct kvm *kvm, unsigned long gpa)
+{
+ unsigned long src_pfn, dst_pfn = 0;
+ struct migrate_vma mig;
+ struct page *dpage, *spage;
+ struct kvmppc_uvmem_page_pvt *pvt;
+ unsigned long pfn;
+ int ret = U_SUCCESS;
+
+ memset(&mig, 0, sizeof(mig));
+ mig.vma = vma;
+ mig.start = start;
+ mig.end = end;
+ mig.src = &src_pfn;
+ mig.dst = &dst_pfn;
+ mig.src_owner = &kvmppc_uvmem_pgmap;
+
+ /* The requested page is already paged-out, nothing to do */
+ if (!kvmppc_gfn_is_uvmem_pfn(gpa >> page_shift, kvm, NULL))
+ return ret;
+
+ ret = migrate_vma_setup(&mig);
+ if (ret)
+ return -1;
+
+ spage = migrate_pfn_to_page(*mig.src);
+ if (!spage || !(*mig.src & MIGRATE_PFN_MIGRATE))
+ goto out_finalize;
+
+ if (!is_zone_device_page(spage))
+ goto out_finalize;
+
+ dpage = alloc_page_vma(GFP_HIGHUSER, vma, start);
+ if (!dpage) {
+ ret = -1;
+ goto out_finalize;
+ }
+
+ lock_page(dpage);
+ pvt = spage->zone_device_data;
+ pfn = page_to_pfn(dpage);
+
+ /*
+ * This function is used in two cases:
+ * - When HV touches a secure page, for which we do UV_PAGE_OUT
+ * - When a secure page is converted to shared page, we *get*
+ * the page to essentially unmap the device page. In this
+ * case we skip page-out.
+ */
+ if (!pvt->skip_page_out)
+ ret = uv_page_out(kvm->arch.lpid, pfn << page_shift,
+ gpa, 0, page_shift);
+
+ if (ret == U_SUCCESS)
+ *mig.dst = migrate_pfn(pfn) | MIGRATE_PFN_LOCKED;
+ else {
+ unlock_page(dpage);
+ __free_page(dpage);
+ goto out_finalize;
+ }
+
+ migrate_vma_pages(&mig);
+
+out_finalize:
+ migrate_vma_finalize(&mig);
+ return ret;
+}
+
+static inline int kvmppc_svm_page_out(struct vm_area_struct *vma,
+ unsigned long start, unsigned long end,
+ unsigned long page_shift,
+ struct kvm *kvm, unsigned long gpa)
+{
+ int ret;
+
+ mutex_lock(&kvm->arch.uvmem_lock);
+ ret = __kvmppc_svm_page_out(vma, start, end, page_shift, kvm, gpa);
+ mutex_unlock(&kvm->arch.uvmem_lock);
+
+ return ret;
+}
+
/*
* Drop device pages that we maintain for the secure guest
*
@@ -898,82 +988,6 @@ unsigned long kvmppc_h_svm_page_in(struct kvm *kvm, unsigned long gpa,
return ret;
}

-/*
- * Provision a new page on HV side and copy over the contents
- * from secure memory using UV_PAGE_OUT uvcall.
- */
-static int kvmppc_svm_page_out(struct vm_area_struct *vma,
- unsigned long start,
- unsigned long end, unsigned long page_shift,
- struct kvm *kvm, unsigned long gpa)
-{
- unsigned long src_pfn, dst_pfn = 0;
- struct migrate_vma mig;
- struct page *dpage, *spage;
- struct kvmppc_uvmem_page_pvt *pvt;
- unsigned long pfn;
- int ret = U_SUCCESS;
-
- memset(&mig, 0, sizeof(mig));
- mig.vma = vma;
- mig.start = start;
- mig.end = end;
- mig.src = &src_pfn;
- mig.dst = &dst_pfn;
- mig.src_owner = &kvmppc_uvmem_pgmap;
-
- mutex_lock(&kvm->arch.uvmem_lock);
- /* The requested page is already paged-out, nothing to do */
- if (!kvmppc_gfn_is_uvmem_pfn(gpa >> page_shift, kvm, NULL))
- goto out;
-
- ret = migrate_vma_setup(&mig);
- if (ret)
- goto out;
-
- spage = migrate_pfn_to_page(*mig.src);
- if (!spage || !(*mig.src & MIGRATE_PFN_MIGRATE))
- goto out_finalize;
-
- if (!is_zone_device_page(spage))
- goto out_finalize;
-
- dpage = alloc_page_vma(GFP_HIGHUSER, vma, start);
- if (!dpage) {
- ret = -1;
- goto out_finalize;
- }
-
- lock_page(dpage);
- pvt = spage->zone_device_data;
- pfn = page_to_pfn(dpage);
-
- /*
- * This function is used in two cases:
- * - When HV touches a secure page, for which we do UV_PAGE_OUT
- * - When a secure page is converted to shared page, we *get*
- * the page to essentially unmap the device page. In this
- * case we skip page-out.
- */
- if (!pvt->skip_page_out)
- ret = uv_page_out(kvm->arch.lpid, pfn << page_shift,
- gpa, 0, page_shift);
-
- if (ret == U_SUCCESS)
- *mig.dst = migrate_pfn(pfn) | MIGRATE_PFN_LOCKED;
- else {
- unlock_page(dpage);
- __free_page(dpage);
- goto out_finalize;
- }
-
- migrate_vma_pages(&mig);
-out_finalize:
- migrate_vma_finalize(&mig);
-out:
- mutex_unlock(&kvm->arch.uvmem_lock);
- return ret;
-}

/*
* Fault handler callback that gets called when HV touches any page that
--
2.27.0
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