[PATCH 4.19 054/220] KVM: PPC: Inform the userspace about TCE update failures

Greg Kroah-Hartman
2019-11-22T10:58:10Z

From: Alexey Kardashevskiy <aik@ozlabs.ru>

[ Upstream commit f7960e299f13f069d6f3d4e157d91bfca2669677 ]

We return H_TOO_HARD from TCE update handlers when we think that
the next handler (realmode -> virtual mode -> user mode) has a chance to
handle the request; H_HARDWARE/H_CLOSED otherwise.

This changes the handlers to return H_TOO_HARD on every error giving
the userspace an opportunity to handle any request or at least log
them all.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
arch/powerpc/kvm/book3s_64_vio.c | 8 ++++----
arch/powerpc/kvm/book3s_64_vio_hv.c | 6 +++---
2 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/arch/powerpc/kvm/book3s_64_vio.c b/arch/powerpc/kvm/book3s_64_vio.c
index 07a8004c3c237..65486c3d029b5 100644
--- a/arch/powerpc/kvm/book3s_64_vio.c
+++ b/arch/powerpc/kvm/book3s_64_vio.c
@@ -401,7 +401,7 @@ static long kvmppc_tce_iommu_do_unmap(struct kvm *kvm,
long ret;

if (WARN_ON_ONCE(iommu_tce_xchg(tbl, entry, &hpa, &dir)))
- return H_HARDWARE;
+ return H_TOO_HARD;

if (dir == DMA_NONE)
return H_SUCCESS;
@@ -449,15 +449,15 @@ long kvmppc_tce_iommu_do_map(struct kvm *kvm, struct iommu_table *tbl,
return H_TOO_HARD;

if (WARN_ON_ONCE(mm_iommu_ua_to_hpa(mem, ua, tbl->it_page_shift, &hpa)))
- return H_HARDWARE;
+ return H_TOO_HARD;

if (mm_iommu_mapped_inc(mem))
- return H_CLOSED;
+ return H_TOO_HARD;

ret = iommu_tce_xchg(tbl, entry, &hpa, &dir);
if (WARN_ON_ONCE(ret)) {
mm_iommu_mapped_dec(mem);
- return H_HARDWARE;
+ return H_TOO_HARD;
}

if (dir != DMA_NONE)
diff --git a/arch/powerpc/kvm/book3s_64_vio_hv.c b/arch/powerpc/kvm/book3s_64_vio_hv.c
index eb8b11515a7ff..d258ed4ef77c3 100644
--- a/arch/powerpc/kvm/book3s_64_vio_hv.c
+++ b/arch/powerpc/kvm/book3s_64_vio_hv.c
@@ -300,10 +300,10 @@ static long kvmppc_rm_tce_iommu_do_map(struct kvm *kvm, struct iommu_table *tbl,

if (WARN_ON_ONCE_RM(mm_iommu_ua_to_hpa_rm(mem, ua, tbl->it_page_shift,
&hpa)))
- return H_HARDWARE;
+ return H_TOO_HARD;

if (WARN_ON_ONCE_RM(mm_iommu_mapped_inc(mem)))
- return H_CLOSED;
+ return H_TOO_HARD;

ret = iommu_tce_xchg_rm(kvm->mm, tbl, entry, &hpa, &dir);
if (ret) {
@@ -501,7 +501,7 @@ long kvmppc_rm_h_put_tce_indirect(struct kvm_vcpu *vcpu,

rmap = (void *) vmalloc_to_phys(rmap);
if (WARN_ON_ONCE_RM(!rmap))
- return H_HARDWARE;
+ return H_TOO_HARD;

/*
* Synchronize with the MMU notifier callbacks in
--
2.20.1