[PATCH v5.5 25/30] KVM: s390: Introduce kvm_s390_get_gfn_end()

From: Sean Christopherson
Date: Wed Nov 03 2021 - 20:29:16 EST


From: Maciej S. Szmigiero <maciej.szmigiero@xxxxxxxxxx>

And use it where s390 code would just access the memslot with the highest
gfn directly.

No functional change intended.

Signed-off-by: Maciej S. Szmigiero <maciej.szmigiero@xxxxxxxxxx>
Reviewed-by: Claudio Imbrenda <imbrenda@xxxxxxxxxxxxx>
Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
---
arch/s390/kvm/kvm-s390.c | 2 +-
arch/s390/kvm/kvm-s390.h | 12 ++++++++++++
arch/s390/kvm/pv.c | 4 +---
3 files changed, 14 insertions(+), 4 deletions(-)

diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 4e032e176216..f7cc0853866b 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -2012,7 +2012,7 @@ static int kvm_s390_get_cmma(struct kvm *kvm, struct kvm_s390_cmma_log *args,
if (!ms)
return 0;
next_gfn = kvm_s390_next_dirty_cmma(slots, cur_gfn + 1);
- mem_end = slots->memslots[0].base_gfn + slots->memslots[0].npages;
+ mem_end = kvm_s390_get_gfn_end(slots);

while (args->count < bufsize) {
hva = gfn_to_hva(kvm, cur_gfn);
diff --git a/arch/s390/kvm/kvm-s390.h b/arch/s390/kvm/kvm-s390.h
index 52bc8fbaa60a..207d299d7fea 100644
--- a/arch/s390/kvm/kvm-s390.h
+++ b/arch/s390/kvm/kvm-s390.h
@@ -208,6 +208,18 @@ static inline int kvm_s390_user_cpu_state_ctrl(struct kvm *kvm)
return kvm->arch.user_cpu_state_ctrl != 0;
}

+/* get the end gfn of the last (highest gfn) memslot */
+static inline unsigned long kvm_s390_get_gfn_end(struct kvm_memslots *slots)
+{
+ struct kvm_memory_slot *ms;
+
+ if (WARN_ON(!slots->used_slots))
+ return 0;
+
+ ms = slots->memslots;
+ return ms->base_gfn + ms->npages;
+}
+
/* implemented in pv.c */
int kvm_s390_pv_destroy_cpu(struct kvm_vcpu *vcpu, u16 *rc, u16 *rrc);
int kvm_s390_pv_create_cpu(struct kvm_vcpu *vcpu, u16 *rc, u16 *rrc);
diff --git a/arch/s390/kvm/pv.c b/arch/s390/kvm/pv.c
index c8841f476e91..e51cccfded25 100644
--- a/arch/s390/kvm/pv.c
+++ b/arch/s390/kvm/pv.c
@@ -117,7 +117,6 @@ static int kvm_s390_pv_alloc_vm(struct kvm *kvm)
unsigned long base = uv_info.guest_base_stor_len;
unsigned long virt = uv_info.guest_virt_var_stor_len;
unsigned long npages = 0, vlen = 0;
- struct kvm_memory_slot *memslot;

kvm->arch.pv.stor_var = NULL;
kvm->arch.pv.stor_base = __get_free_pages(GFP_KERNEL_ACCOUNT, get_order(base));
@@ -131,8 +130,7 @@ static int kvm_s390_pv_alloc_vm(struct kvm *kvm)
* Slots are sorted by GFN
*/
mutex_lock(&kvm->slots_lock);
- memslot = kvm_memslots(kvm)->memslots;
- npages = memslot->base_gfn + memslot->npages;
+ npages = kvm_s390_get_gfn_end(kvm_memslots(kvm));
mutex_unlock(&kvm->slots_lock);

kvm->arch.pv.guest_len = npages * PAGE_SIZE;
--
2.33.1.1089.g2158813163f-goog