@@ -4296,7 +4296,12 @@ void kvm_arch_async_page_ready(struct kvm_vcpu *vcpu, struct kvm_async_pf *work)
static int __kvm_faultin_pfn(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault)
{
struct kvm_memory_slot *slot = fault->slot;
- bool async;
+ struct kvm_follow_pfn foll = {
+ .slot = slot,
+ .gfn = fault->gfn,
+ .flags = FOLL_GET | (fault->write ? FOLL_WRITE : 0),
+ .try_map_writable = true,
+ };
/*
* Retry the page fault if the gfn hit a memslot that is being deleted
@@ -4325,12 +4330,20 @@ static int __kvm_faultin_pfn(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault
return RET_PF_EMULATE;
}
- async = false;
- fault->pfn = __gfn_to_pfn_memslot(slot, fault->gfn, false, false, &async,
- fault->write, &fault->map_writable,
- &fault->hva);
- if (!async)
- return RET_PF_CONTINUE; /* *pfn has correct page already */
+ foll.flags |= FOLL_NOWAIT;
+ fault->pfn = __kvm_follow_pfn(&foll);
+
+ if (!is_error_noslot_pfn(fault->pfn))
+ goto success;
+
+ /*
+ * If __kvm_follow_pfn() failed because I/O is needed to fault in the
+ * page, then either set up an asynchronous #PF to do the I/O, or if
+ * doing an async #PF isn't possible, retry __kvm_follow_pfn() with
+ * I/O allowed. All other failures are fatal, i.e. retrying won't help.
+ */
+ if (fault->pfn != KVM_PFN_ERR_NEEDS_IO)
+ return RET_PF_CONTINUE;
if (!fault->prefetch && kvm_can_do_async_pf(vcpu)) {
trace_kvm_try_async_get_page(fault->addr, fault->gfn);
@@ -4348,9 +4361,17 @@ static int __kvm_faultin_pfn(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault
* to wait for IO. Note, gup always bails if it is unable to quickly
* get a page and a fatal signal, i.e. SIGKILL, is pending.
*/
- fault->pfn = __gfn_to_pfn_memslot(slot, fault->gfn, false, true, NULL,
- fault->write, &fault->map_writable,
- &fault->hva);
+ foll.flags |= FOLL_INTERRUPTIBLE;
+ foll.flags &= ~FOLL_NOWAIT;
+ fault->pfn = __kvm_follow_pfn(&foll);
+
+ if (!is_error_noslot_pfn(fault->pfn))
+ goto success;
+
+ return RET_PF_CONTINUE;
+success:
+ fault->hva = foll.hva;
+ fault->map_writable = foll.writable;
return RET_PF_CONTINUE;
}