From 5731aacd54a883dd2c1a5e8c85e1fe78fc728dc7 Mon Sep 17 00:00:00 2001
From: Peter Xu <peterx@redhat.com>
Date: Mon, 26 Aug 2024 16:43:44 -0400
Subject: [PATCH] KVM: use follow_pfnmap API
Use the new pfnmap API to allow huge MMIO mappings for VMs. The rest work
is done perfectly on the other side (host_pfn_mapping_level()).
Link: https://lkml.kernel.org/r/20240826204353.2228736-11-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Alex Williamson <alex.williamson@redhat.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Gavin Shan <gshan@redhat.com>
Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Niklas Schnelle <schnelle@linux.ibm.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
virt/kvm/kvm_main.c | 19 +++++++------------
1 file changed, 7 insertions(+), 12 deletions(-)
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index cb2b78e92910f..f416d5e3f9c0b 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -2860,13 +2860,11 @@ static int hva_to_pfn_remapped(struct vm_area_struct *vma,
unsigned long addr, bool write_fault,
bool *writable, kvm_pfn_t *p_pfn)
{
+ struct follow_pfnmap_args args = { .vma = vma, .address = addr };
kvm_pfn_t pfn;
- pte_t *ptep;
- pte_t pte;
- spinlock_t *ptl;
int r;
- r = follow_pte(vma, addr, &ptep, &ptl);
+ r = follow_pfnmap_start(&args);
if (r) {
/*
* get_user_pages fails for VM_IO and VM_PFNMAP vmas and does
@@ -2881,21 +2879,19 @@ static int hva_to_pfn_remapped(struct vm_area_struct *vma,
if (r)
return r;
- r = follow_pte(vma, addr, &ptep, &ptl);
+ r = follow_pfnmap_start(&args);
if (r)
return r;
}
- pte = ptep_get(ptep);
-
- if (write_fault && !pte_write(pte)) {
+ if (write_fault && !args.writable) {
pfn = KVM_PFN_ERR_RO_FAULT;
goto out;
}
if (writable)
- *writable = pte_write(pte);
- pfn = pte_pfn(pte);
+ *writable = args.writable;
+ pfn = args.pfn;
/*
* Get a reference here because callers of *hva_to_pfn* and
@@ -2916,9 +2912,8 @@ static int hva_to_pfn_remapped(struct vm_area_struct *vma,
*/
if (!kvm_try_get_pfn(pfn))
r = -EFAULT;
-
out:
- pte_unmap_unlock(ptep, ptl);
+ follow_pfnmap_end(&args);
*p_pfn = pfn;
return r;
--
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