* [GIT PULL 01/51] s390/kvm: page table invalidation notifier
2016-06-21 13:12 [GIT PULL 00/51] KVM: s390: vSIE (nested virtualization) feature for 4.8 (kvm/next) Christian Borntraeger
@ 2016-06-21 13:12 ` Christian Borntraeger
2016-06-21 13:12 ` [GIT PULL 02/51] s390/mm: use RCU for gmap notifier list and the per-mm gmap list Christian Borntraeger
` (50 subsequent siblings)
51 siblings, 0 replies; 53+ messages in thread
From: Christian Borntraeger @ 2016-06-21 13:12 UTC (permalink / raw)
To: Paolo Bonzini, Radim Krčmář
Cc: KVM, Cornelia Huck, linux-s390, Christian Borntraeger,
David Hildenbrand, Martin Schwidefsky
From: Martin Schwidefsky <schwidefsky@de.ibm.com>
Pass an address range to the page table invalidation notifier
for KVM. This allows to notify changes that affect a larger
virtual memory area, e.g. for 1MB pages.
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
arch/s390/include/asm/gmap.h | 3 ++-
arch/s390/kvm/kvm-s390.c | 18 +++++++++++++-----
arch/s390/mm/gmap.c | 19 ++++++++++++++++---
3 files changed, 31 insertions(+), 9 deletions(-)
diff --git a/arch/s390/include/asm/gmap.h b/arch/s390/include/asm/gmap.h
index d054c1b..bc0eadf 100644
--- a/arch/s390/include/asm/gmap.h
+++ b/arch/s390/include/asm/gmap.h
@@ -39,7 +39,8 @@ struct gmap {
*/
struct gmap_notifier {
struct list_head list;
- void (*notifier_call)(struct gmap *gmap, unsigned long gaddr);
+ void (*notifier_call)(struct gmap *gmap, unsigned long start,
+ unsigned long end);
};
struct gmap *gmap_alloc(struct mm_struct *mm, unsigned long limit);
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 0dcf9b8..67f1b6b 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -150,7 +150,8 @@ int kvm_arch_hardware_enable(void)
return 0;
}
-static void kvm_gmap_notifier(struct gmap *gmap, unsigned long address);
+static void kvm_gmap_notifier(struct gmap *gmap, unsigned long start,
+ unsigned long end);
/*
* This callback is executed during stop_machine(). All CPUs are therefore
@@ -1976,16 +1977,23 @@ void kvm_s390_sync_request(int req, struct kvm_vcpu *vcpu)
kvm_s390_vcpu_request(vcpu);
}
-static void kvm_gmap_notifier(struct gmap *gmap, unsigned long address)
+static void kvm_gmap_notifier(struct gmap *gmap, unsigned long start,
+ unsigned long end)
{
- int i;
struct kvm *kvm = gmap->private;
struct kvm_vcpu *vcpu;
+ unsigned long prefix;
+ int i;
+ if (start >= 1UL << 31)
+ /* We are only interested in prefix pages */
+ return;
kvm_for_each_vcpu(i, vcpu, kvm) {
/* match against both prefix pages */
- if (kvm_s390_get_prefix(vcpu) == (address & ~0x1000UL)) {
- VCPU_EVENT(vcpu, 2, "gmap notifier for %lx", address);
+ prefix = kvm_s390_get_prefix(vcpu);
+ if (prefix <= end && start <= prefix + 2*PAGE_SIZE - 1) {
+ VCPU_EVENT(vcpu, 2, "gmap notifier for %lx-%lx",
+ start, end);
kvm_s390_sync_request(KVM_REQ_MMU_RELOAD, vcpu);
}
}
diff --git a/arch/s390/mm/gmap.c b/arch/s390/mm/gmap.c
index cace818..b5820bf 100644
--- a/arch/s390/mm/gmap.c
+++ b/arch/s390/mm/gmap.c
@@ -573,6 +573,21 @@ void gmap_unregister_ipte_notifier(struct gmap_notifier *nb)
EXPORT_SYMBOL_GPL(gmap_unregister_ipte_notifier);
/**
+ * gmap_call_notifier - call all registered invalidation callbacks
+ * @gmap: pointer to guest mapping meta data structure
+ * @start: start virtual address in the guest address space
+ * @end: end virtual address in the guest address space
+ */
+static void gmap_call_notifier(struct gmap *gmap, unsigned long start,
+ unsigned long end)
+{
+ struct gmap_notifier *nb;
+
+ list_for_each_entry(nb, &gmap_notifier_list, list)
+ nb->notifier_call(gmap, start, end);
+}
+
+/**
* gmap_ipte_notify - mark a range of ptes for invalidation notification
* @gmap: pointer to guest mapping meta data structure
* @gaddr: virtual address in the guest address space
@@ -643,7 +658,6 @@ void ptep_notify(struct mm_struct *mm, unsigned long vmaddr, pte_t *pte)
{
unsigned long offset, gaddr;
unsigned long *table;
- struct gmap_notifier *nb;
struct gmap *gmap;
offset = ((unsigned long) pte) & (255 * sizeof(pte_t));
@@ -655,8 +669,7 @@ void ptep_notify(struct mm_struct *mm, unsigned long vmaddr, pte_t *pte)
if (!table)
continue;
gaddr = __gmap_segment_gaddr(table) + offset;
- list_for_each_entry(nb, &gmap_notifier_list, list)
- nb->notifier_call(gmap, gaddr);
+ gmap_call_notifier(gmap, gaddr, gaddr + PAGE_SIZE - 1);
}
spin_unlock(&gmap_notifier_lock);
}
--
2.5.5
^ permalink raw reply related [flat|nested] 53+ messages in thread* [GIT PULL 02/51] s390/mm: use RCU for gmap notifier list and the per-mm gmap list
2016-06-21 13:12 [GIT PULL 00/51] KVM: s390: vSIE (nested virtualization) feature for 4.8 (kvm/next) Christian Borntraeger
2016-06-21 13:12 ` [GIT PULL 01/51] s390/kvm: page table invalidation notifier Christian Borntraeger
@ 2016-06-21 13:12 ` Christian Borntraeger
2016-06-21 13:12 ` [GIT PULL 03/51] s390/mm: extended gmap pte notifier Christian Borntraeger
` (49 subsequent siblings)
51 siblings, 0 replies; 53+ messages in thread
From: Christian Borntraeger @ 2016-06-21 13:12 UTC (permalink / raw)
To: Paolo Bonzini, Radim Krčmář
Cc: KVM, Cornelia Huck, linux-s390, Christian Borntraeger,
David Hildenbrand, Martin Schwidefsky
From: Martin Schwidefsky <schwidefsky@de.ibm.com>
The gmap notifier list and the gmap list in the mm_struct change rarely.
Use RCU to optimize the reader of these lists.
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
arch/s390/include/asm/gmap.h | 1 +
arch/s390/include/asm/mmu.h | 11 +++++++----
arch/s390/include/asm/mmu_context.h | 3 ++-
arch/s390/mm/gmap.c | 39 ++++++++++++++++++++++---------------
arch/s390/mm/pgalloc.c | 16 +++++++--------
5 files changed, 41 insertions(+), 29 deletions(-)
diff --git a/arch/s390/include/asm/gmap.h b/arch/s390/include/asm/gmap.h
index bc0eadf..2cf49624 100644
--- a/arch/s390/include/asm/gmap.h
+++ b/arch/s390/include/asm/gmap.h
@@ -39,6 +39,7 @@ struct gmap {
*/
struct gmap_notifier {
struct list_head list;
+ struct rcu_head rcu;
void (*notifier_call)(struct gmap *gmap, unsigned long start,
unsigned long end);
};
diff --git a/arch/s390/include/asm/mmu.h b/arch/s390/include/asm/mmu.h
index 081b2ad..b941528 100644
--- a/arch/s390/include/asm/mmu.h
+++ b/arch/s390/include/asm/mmu.h
@@ -8,8 +8,9 @@ typedef struct {
cpumask_t cpu_attach_mask;
atomic_t attach_count;
unsigned int flush_mm;
- spinlock_t list_lock;
+ spinlock_t pgtable_lock;
struct list_head pgtable_list;
+ spinlock_t gmap_lock;
struct list_head gmap_list;
unsigned long asce;
unsigned long asce_limit;
@@ -22,9 +23,11 @@ typedef struct {
unsigned int use_skey:1;
} mm_context_t;
-#define INIT_MM_CONTEXT(name) \
- .context.list_lock = __SPIN_LOCK_UNLOCKED(name.context.list_lock), \
- .context.pgtable_list = LIST_HEAD_INIT(name.context.pgtable_list), \
+#define INIT_MM_CONTEXT(name) \
+ .context.pgtable_lock = \
+ __SPIN_LOCK_UNLOCKED(name.context.pgtable_lock), \
+ .context.pgtable_list = LIST_HEAD_INIT(name.context.pgtable_list), \
+ .context.gmap_lock = __SPIN_LOCK_UNLOCKED(name.context.gmap_lock), \
.context.gmap_list = LIST_HEAD_INIT(name.context.gmap_list),
static inline int tprot(unsigned long addr)
diff --git a/arch/s390/include/asm/mmu_context.h b/arch/s390/include/asm/mmu_context.h
index c837b79..3ce3854 100644
--- a/arch/s390/include/asm/mmu_context.h
+++ b/arch/s390/include/asm/mmu_context.h
@@ -15,8 +15,9 @@
static inline int init_new_context(struct task_struct *tsk,
struct mm_struct *mm)
{
- spin_lock_init(&mm->context.list_lock);
+ spin_lock_init(&mm->context.pgtable_lock);
INIT_LIST_HEAD(&mm->context.pgtable_list);
+ spin_lock_init(&mm->context.gmap_lock);
INIT_LIST_HEAD(&mm->context.gmap_list);
cpumask_clear(&mm->context.cpu_attach_mask);
atomic_set(&mm->context.attach_count, 0);
diff --git a/arch/s390/mm/gmap.c b/arch/s390/mm/gmap.c
index b5820bf..8b56423 100644
--- a/arch/s390/mm/gmap.c
+++ b/arch/s390/mm/gmap.c
@@ -70,9 +70,9 @@ struct gmap *gmap_alloc(struct mm_struct *mm, unsigned long limit)
gmap->asce = atype | _ASCE_TABLE_LENGTH |
_ASCE_USER_BITS | __pa(table);
gmap->asce_end = limit;
- down_write(&mm->mmap_sem);
- list_add(&gmap->list, &mm->context.gmap_list);
- up_write(&mm->mmap_sem);
+ spin_lock(&mm->context.gmap_lock);
+ list_add_rcu(&gmap->list, &mm->context.gmap_list);
+ spin_unlock(&mm->context.gmap_lock);
return gmap;
out_free:
@@ -128,14 +128,16 @@ void gmap_free(struct gmap *gmap)
else
__tlb_flush_global();
+ spin_lock(&gmap->mm->context.gmap_lock);
+ list_del_rcu(&gmap->list);
+ spin_unlock(&gmap->mm->context.gmap_lock);
+ synchronize_rcu();
+
/* Free all segment & region tables. */
list_for_each_entry_safe(page, next, &gmap->crst_list, lru)
__free_pages(page, 2);
gmap_radix_tree_free(&gmap->guest_to_host);
gmap_radix_tree_free(&gmap->host_to_guest);
- down_write(&gmap->mm->mmap_sem);
- list_del(&gmap->list);
- up_write(&gmap->mm->mmap_sem);
kfree(gmap);
}
EXPORT_SYMBOL_GPL(gmap_free);
@@ -369,11 +371,13 @@ void gmap_unlink(struct mm_struct *mm, unsigned long *table,
struct gmap *gmap;
int flush;
- list_for_each_entry(gmap, &mm->context.gmap_list, list) {
+ rcu_read_lock();
+ list_for_each_entry_rcu(gmap, &mm->context.gmap_list, list) {
flush = __gmap_unlink_by_vmaddr(gmap, vmaddr);
if (flush)
gmap_flush_tlb(gmap);
}
+ rcu_read_unlock();
}
/**
@@ -555,7 +559,7 @@ static DEFINE_SPINLOCK(gmap_notifier_lock);
void gmap_register_ipte_notifier(struct gmap_notifier *nb)
{
spin_lock(&gmap_notifier_lock);
- list_add(&nb->list, &gmap_notifier_list);
+ list_add_rcu(&nb->list, &gmap_notifier_list);
spin_unlock(&gmap_notifier_lock);
}
EXPORT_SYMBOL_GPL(gmap_register_ipte_notifier);
@@ -567,8 +571,9 @@ EXPORT_SYMBOL_GPL(gmap_register_ipte_notifier);
void gmap_unregister_ipte_notifier(struct gmap_notifier *nb)
{
spin_lock(&gmap_notifier_lock);
- list_del_init(&nb->list);
+ list_del_rcu(&nb->list);
spin_unlock(&gmap_notifier_lock);
+ synchronize_rcu();
}
EXPORT_SYMBOL_GPL(gmap_unregister_ipte_notifier);
@@ -662,16 +667,18 @@ void ptep_notify(struct mm_struct *mm, unsigned long vmaddr, pte_t *pte)
offset = ((unsigned long) pte) & (255 * sizeof(pte_t));
offset = offset * (4096 / sizeof(pte_t));
- spin_lock(&gmap_notifier_lock);
- list_for_each_entry(gmap, &mm->context.gmap_list, list) {
+ rcu_read_lock();
+ list_for_each_entry_rcu(gmap, &mm->context.gmap_list, list) {
+ spin_lock(&gmap->guest_table_lock);
table = radix_tree_lookup(&gmap->host_to_guest,
vmaddr >> PMD_SHIFT);
- if (!table)
- continue;
- gaddr = __gmap_segment_gaddr(table) + offset;
- gmap_call_notifier(gmap, gaddr, gaddr + PAGE_SIZE - 1);
+ if (table)
+ gaddr = __gmap_segment_gaddr(table) + offset;
+ spin_unlock(&gmap->guest_table_lock);
+ if (table)
+ gmap_call_notifier(gmap, gaddr, gaddr + PAGE_SIZE - 1);
}
- spin_unlock(&gmap_notifier_lock);
+ rcu_read_unlock();
}
EXPORT_SYMBOL_GPL(ptep_notify);
diff --git a/arch/s390/mm/pgalloc.c b/arch/s390/mm/pgalloc.c
index e8b5962..7be1f94 100644
--- a/arch/s390/mm/pgalloc.c
+++ b/arch/s390/mm/pgalloc.c
@@ -149,7 +149,7 @@ unsigned long *page_table_alloc(struct mm_struct *mm)
/* Try to get a fragment of a 4K page as a 2K page table */
if (!mm_alloc_pgste(mm)) {
table = NULL;
- spin_lock_bh(&mm->context.list_lock);
+ spin_lock_bh(&mm->context.pgtable_lock);
if (!list_empty(&mm->context.pgtable_list)) {
page = list_first_entry(&mm->context.pgtable_list,
struct page, lru);
@@ -164,7 +164,7 @@ unsigned long *page_table_alloc(struct mm_struct *mm)
list_del(&page->lru);
}
}
- spin_unlock_bh(&mm->context.list_lock);
+ spin_unlock_bh(&mm->context.pgtable_lock);
if (table)
return table;
}
@@ -187,9 +187,9 @@ unsigned long *page_table_alloc(struct mm_struct *mm)
/* Return the first 2K fragment of the page */
atomic_set(&page->_mapcount, 1);
clear_table(table, _PAGE_INVALID, PAGE_SIZE);
- spin_lock_bh(&mm->context.list_lock);
+ spin_lock_bh(&mm->context.pgtable_lock);
list_add(&page->lru, &mm->context.pgtable_list);
- spin_unlock_bh(&mm->context.list_lock);
+ spin_unlock_bh(&mm->context.pgtable_lock);
}
return table;
}
@@ -203,13 +203,13 @@ void page_table_free(struct mm_struct *mm, unsigned long *table)
if (!mm_alloc_pgste(mm)) {
/* Free 2K page table fragment of a 4K page */
bit = (__pa(table) & ~PAGE_MASK)/(PTRS_PER_PTE*sizeof(pte_t));
- spin_lock_bh(&mm->context.list_lock);
+ spin_lock_bh(&mm->context.pgtable_lock);
mask = atomic_xor_bits(&page->_mapcount, 1U << bit);
if (mask & 3)
list_add(&page->lru, &mm->context.pgtable_list);
else
list_del(&page->lru);
- spin_unlock_bh(&mm->context.list_lock);
+ spin_unlock_bh(&mm->context.pgtable_lock);
if (mask != 0)
return;
}
@@ -235,13 +235,13 @@ void page_table_free_rcu(struct mmu_gather *tlb, unsigned long *table,
return;
}
bit = (__pa(table) & ~PAGE_MASK) / (PTRS_PER_PTE*sizeof(pte_t));
- spin_lock_bh(&mm->context.list_lock);
+ spin_lock_bh(&mm->context.pgtable_lock);
mask = atomic_xor_bits(&page->_mapcount, 0x11U << bit);
if (mask & 3)
list_add_tail(&page->lru, &mm->context.pgtable_list);
else
list_del(&page->lru);
- spin_unlock_bh(&mm->context.list_lock);
+ spin_unlock_bh(&mm->context.pgtable_lock);
table = (unsigned long *) (__pa(table) | (1U << bit));
tlb_remove_table(tlb, table);
}
--
2.5.5
^ permalink raw reply related [flat|nested] 53+ messages in thread* [GIT PULL 03/51] s390/mm: extended gmap pte notifier
2016-06-21 13:12 [GIT PULL 00/51] KVM: s390: vSIE (nested virtualization) feature for 4.8 (kvm/next) Christian Borntraeger
2016-06-21 13:12 ` [GIT PULL 01/51] s390/kvm: page table invalidation notifier Christian Borntraeger
2016-06-21 13:12 ` [GIT PULL 02/51] s390/mm: use RCU for gmap notifier list and the per-mm gmap list Christian Borntraeger
@ 2016-06-21 13:12 ` Christian Borntraeger
2016-06-21 13:12 ` [GIT PULL 04/51] s390/mm: add reference counter to gmap structure Christian Borntraeger
` (48 subsequent siblings)
51 siblings, 0 replies; 53+ messages in thread
From: Christian Borntraeger @ 2016-06-21 13:12 UTC (permalink / raw)
To: Paolo Bonzini, Radim Krčmář
Cc: KVM, Cornelia Huck, linux-s390, Christian Borntraeger,
David Hildenbrand, Martin Schwidefsky
From: Martin Schwidefsky <schwidefsky@de.ibm.com>
The current gmap pte notifier forces a pte into to a read-write state.
If the pte is invalidated the gmap notifier is called to inform KVM
that the mapping will go away.
Extend this approach to allow read-write, read-only and no-access
as possible target states and call the pte notifier for any change
to the pte.
This mechanism is used to temporarily set specific access rights for
a pte without doing the heavy work of a true mprotect call.
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
arch/s390/include/asm/gmap.h | 9 ++-
arch/s390/include/asm/pgtable.h | 2 +
arch/s390/kvm/kvm-s390.c | 13 +--
arch/s390/mm/gmap.c | 170 ++++++++++++++++++++++++++++++----------
arch/s390/mm/pgtable.c | 54 +++++++++++--
5 files changed, 193 insertions(+), 55 deletions(-)
diff --git a/arch/s390/include/asm/gmap.h b/arch/s390/include/asm/gmap.h
index 2cf49624..6897a09 100644
--- a/arch/s390/include/asm/gmap.h
+++ b/arch/s390/include/asm/gmap.h
@@ -59,8 +59,11 @@ void gmap_discard(struct gmap *, unsigned long from, unsigned long to);
void __gmap_zap(struct gmap *, unsigned long gaddr);
void gmap_unlink(struct mm_struct *, unsigned long *table, unsigned long vmaddr);
-void gmap_register_ipte_notifier(struct gmap_notifier *);
-void gmap_unregister_ipte_notifier(struct gmap_notifier *);
-int gmap_ipte_notify(struct gmap *, unsigned long start, unsigned long len);
+void gmap_register_pte_notifier(struct gmap_notifier *);
+void gmap_unregister_pte_notifier(struct gmap_notifier *);
+void gmap_pte_notify(struct mm_struct *, unsigned long addr, pte_t *);
+
+int gmap_mprotect_notify(struct gmap *, unsigned long start,
+ unsigned long len, int prot);
#endif /* _ASM_S390_GMAP_H */
diff --git a/arch/s390/include/asm/pgtable.h b/arch/s390/include/asm/pgtable.h
index 9951e7e..35dde6a 100644
--- a/arch/s390/include/asm/pgtable.h
+++ b/arch/s390/include/asm/pgtable.h
@@ -886,6 +886,8 @@ void ptep_set_pte_at(struct mm_struct *mm, unsigned long addr,
pte_t *ptep, pte_t entry);
void ptep_set_notify(struct mm_struct *mm, unsigned long addr, pte_t *ptep);
void ptep_notify(struct mm_struct *mm, unsigned long addr, pte_t *ptep);
+int ptep_force_prot(struct mm_struct *mm, unsigned long gaddr,
+ pte_t *ptep, int prot);
void ptep_zap_unused(struct mm_struct *mm, unsigned long addr,
pte_t *ptep , int reset);
void ptep_zap_key(struct mm_struct *mm, unsigned long addr, pte_t *ptep);
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 67f1b6b..b6e7f66 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -21,6 +21,7 @@
#include <linux/init.h>
#include <linux/kvm.h>
#include <linux/kvm_host.h>
+#include <linux/mman.h>
#include <linux/module.h>
#include <linux/random.h>
#include <linux/slab.h>
@@ -185,7 +186,7 @@ static struct notifier_block kvm_clock_notifier = {
int kvm_arch_hardware_setup(void)
{
gmap_notifier.notifier_call = kvm_gmap_notifier;
- gmap_register_ipte_notifier(&gmap_notifier);
+ gmap_register_pte_notifier(&gmap_notifier);
atomic_notifier_chain_register(&s390_epoch_delta_notifier,
&kvm_clock_notifier);
return 0;
@@ -193,7 +194,7 @@ int kvm_arch_hardware_setup(void)
void kvm_arch_hardware_unsetup(void)
{
- gmap_unregister_ipte_notifier(&gmap_notifier);
+ gmap_unregister_pte_notifier(&gmap_notifier);
atomic_notifier_chain_unregister(&s390_epoch_delta_notifier,
&kvm_clock_notifier);
}
@@ -2272,16 +2273,16 @@ retry:
return 0;
/*
* We use MMU_RELOAD just to re-arm the ipte notifier for the
- * guest prefix page. gmap_ipte_notify will wait on the ptl lock.
+ * guest prefix page. gmap_mprotect_notify will wait on the ptl lock.
* This ensures that the ipte instruction for this request has
* already finished. We might race against a second unmapper that
* wants to set the blocking bit. Lets just retry the request loop.
*/
if (kvm_check_request(KVM_REQ_MMU_RELOAD, vcpu)) {
int rc;
- rc = gmap_ipte_notify(vcpu->arch.gmap,
- kvm_s390_get_prefix(vcpu),
- PAGE_SIZE * 2);
+ rc = gmap_mprotect_notify(vcpu->arch.gmap,
+ kvm_s390_get_prefix(vcpu),
+ PAGE_SIZE * 2, PROT_WRITE);
if (rc)
return rc;
goto retry;
diff --git a/arch/s390/mm/gmap.c b/arch/s390/mm/gmap.c
index 8b56423..480c076 100644
--- a/arch/s390/mm/gmap.c
+++ b/arch/s390/mm/gmap.c
@@ -553,29 +553,29 @@ static LIST_HEAD(gmap_notifier_list);
static DEFINE_SPINLOCK(gmap_notifier_lock);
/**
- * gmap_register_ipte_notifier - register a pte invalidation callback
+ * gmap_register_pte_notifier - register a pte invalidation callback
* @nb: pointer to the gmap notifier block
*/
-void gmap_register_ipte_notifier(struct gmap_notifier *nb)
+void gmap_register_pte_notifier(struct gmap_notifier *nb)
{
spin_lock(&gmap_notifier_lock);
list_add_rcu(&nb->list, &gmap_notifier_list);
spin_unlock(&gmap_notifier_lock);
}
-EXPORT_SYMBOL_GPL(gmap_register_ipte_notifier);
+EXPORT_SYMBOL_GPL(gmap_register_pte_notifier);
/**
- * gmap_unregister_ipte_notifier - remove a pte invalidation callback
+ * gmap_unregister_pte_notifier - remove a pte invalidation callback
* @nb: pointer to the gmap notifier block
*/
-void gmap_unregister_ipte_notifier(struct gmap_notifier *nb)
+void gmap_unregister_pte_notifier(struct gmap_notifier *nb)
{
spin_lock(&gmap_notifier_lock);
list_del_rcu(&nb->list);
spin_unlock(&gmap_notifier_lock);
synchronize_rcu();
}
-EXPORT_SYMBOL_GPL(gmap_unregister_ipte_notifier);
+EXPORT_SYMBOL_GPL(gmap_unregister_pte_notifier);
/**
* gmap_call_notifier - call all registered invalidation callbacks
@@ -593,62 +593,150 @@ static void gmap_call_notifier(struct gmap *gmap, unsigned long start,
}
/**
- * gmap_ipte_notify - mark a range of ptes for invalidation notification
+ * gmap_table_walk - walk the gmap page tables
+ * @gmap: pointer to guest mapping meta data structure
+ * @gaddr: virtual address in the guest address space
+ *
+ * Returns a table pointer for the given guest address.
+ */
+static inline unsigned long *gmap_table_walk(struct gmap *gmap,
+ unsigned long gaddr)
+{
+ unsigned long *table;
+
+ table = gmap->table;
+ switch (gmap->asce & _ASCE_TYPE_MASK) {
+ case _ASCE_TYPE_REGION1:
+ table += (gaddr >> 53) & 0x7ff;
+ if (*table & _REGION_ENTRY_INVALID)
+ return NULL;
+ table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN);
+ /* Fallthrough */
+ case _ASCE_TYPE_REGION2:
+ table += (gaddr >> 42) & 0x7ff;
+ if (*table & _REGION_ENTRY_INVALID)
+ return NULL;
+ table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN);
+ /* Fallthrough */
+ case _ASCE_TYPE_REGION3:
+ table += (gaddr >> 31) & 0x7ff;
+ if (*table & _REGION_ENTRY_INVALID)
+ return NULL;
+ table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN);
+ /* Fallthrough */
+ case _ASCE_TYPE_SEGMENT:
+ table += (gaddr >> 20) & 0x7ff;
+ }
+ return table;
+}
+
+/**
+ * gmap_pte_op_walk - walk the gmap page table, get the page table lock
+ * and return the pte pointer
+ * @gmap: pointer to guest mapping meta data structure
+ * @gaddr: virtual address in the guest address space
+ * @ptl: pointer to the spinlock pointer
+ *
+ * Returns a pointer to the locked pte for a guest address, or NULL
+ */
+static pte_t *gmap_pte_op_walk(struct gmap *gmap, unsigned long gaddr,
+ spinlock_t **ptl)
+{
+ unsigned long *table;
+
+ /* Walk the gmap page table, lock and get pte pointer */
+ table = gmap_table_walk(gmap, gaddr);
+ if (!table || *table & _SEGMENT_ENTRY_INVALID)
+ return NULL;
+ return pte_alloc_map_lock(gmap->mm, (pmd_t *) table, gaddr, ptl);
+}
+
+/**
+ * gmap_pte_op_fixup - force a page in and connect the gmap page table
+ * @gmap: pointer to guest mapping meta data structure
+ * @gaddr: virtual address in the guest address space
+ * @vmaddr: address in the host process address space
+ *
+ * Returns 0 if the caller can retry __gmap_translate (might fail again),
+ * -ENOMEM if out of memory and -EFAULT if anything goes wrong while fixing
+ * up or connecting the gmap page table.
+ */
+static int gmap_pte_op_fixup(struct gmap *gmap, unsigned long gaddr,
+ unsigned long vmaddr)
+{
+ struct mm_struct *mm = gmap->mm;
+ bool unlocked = false;
+
+ if (fixup_user_fault(current, mm, vmaddr, FAULT_FLAG_WRITE, &unlocked))
+ return -EFAULT;
+ if (unlocked)
+ /* lost mmap_sem, caller has to retry __gmap_translate */
+ return 0;
+ /* Connect the page tables */
+ return __gmap_link(gmap, gaddr, vmaddr);
+}
+
+/**
+ * gmap_pte_op_end - release the page table lock
+ * @ptl: pointer to the spinlock pointer
+ */
+static void gmap_pte_op_end(spinlock_t *ptl)
+{
+ spin_unlock(ptl);
+}
+
+/**
+ * gmap_mprotect_notify - change access rights for a range of ptes and
+ * call the notifier if any pte changes again
* @gmap: pointer to guest mapping meta data structure
* @gaddr: virtual address in the guest address space
* @len: size of area
+ * @prot: indicates access rights: PROT_NONE, PROT_READ or PROT_WRITE
*
- * Returns 0 if for each page in the given range a gmap mapping exists and
- * the invalidation notification could be set. If the gmap mapping is missing
- * for one or more pages -EFAULT is returned. If no memory could be allocated
- * -ENOMEM is returned. This function establishes missing page table entries.
+ * Returns 0 if for each page in the given range a gmap mapping exists,
+ * the new access rights could be set and the notifier could be armed.
+ * If the gmap mapping is missing for one or more pages -EFAULT is
+ * returned. If no memory could be allocated -ENOMEM is returned.
+ * This function establishes missing page table entries.
*/
-int gmap_ipte_notify(struct gmap *gmap, unsigned long gaddr, unsigned long len)
+int gmap_mprotect_notify(struct gmap *gmap, unsigned long gaddr,
+ unsigned long len, int prot)
{
- unsigned long addr;
+ unsigned long vmaddr;
spinlock_t *ptl;
pte_t *ptep;
- bool unlocked;
int rc = 0;
if ((gaddr & ~PAGE_MASK) || (len & ~PAGE_MASK))
return -EINVAL;
+ if (!MACHINE_HAS_ESOP && prot == PROT_READ)
+ return -EINVAL;
down_read(&gmap->mm->mmap_sem);
while (len) {
- unlocked = false;
- /* Convert gmap address and connect the page tables */
- addr = __gmap_translate(gmap, gaddr);
- if (IS_ERR_VALUE(addr)) {
- rc = addr;
- break;
+ rc = -EAGAIN;
+ ptep = gmap_pte_op_walk(gmap, gaddr, &ptl);
+ if (ptep) {
+ rc = ptep_force_prot(gmap->mm, gaddr, ptep, prot);
+ gmap_pte_op_end(ptl);
}
- /* Get the page mapped */
- if (fixup_user_fault(current, gmap->mm, addr, FAULT_FLAG_WRITE,
- &unlocked)) {
- rc = -EFAULT;
- break;
- }
- /* While trying to map mmap_sem got unlocked. Let us retry */
- if (unlocked)
+ if (rc) {
+ vmaddr = __gmap_translate(gmap, gaddr);
+ if (IS_ERR_VALUE(vmaddr)) {
+ rc = vmaddr;
+ break;
+ }
+ rc = gmap_pte_op_fixup(gmap, gaddr, vmaddr);
+ if (rc)
+ break;
continue;
- rc = __gmap_link(gmap, gaddr, addr);
- if (rc)
- break;
- /* Walk the process page table, lock and get pte pointer */
- ptep = get_locked_pte(gmap->mm, addr, &ptl);
- VM_BUG_ON(!ptep);
- /* Set notification bit in the pgste of the pte */
- if ((pte_val(*ptep) & (_PAGE_INVALID | _PAGE_PROTECT)) == 0) {
- ptep_set_notify(gmap->mm, addr, ptep);
- gaddr += PAGE_SIZE;
- len -= PAGE_SIZE;
}
- pte_unmap_unlock(ptep, ptl);
+ gaddr += PAGE_SIZE;
+ len -= PAGE_SIZE;
}
up_read(&gmap->mm->mmap_sem);
return rc;
}
-EXPORT_SYMBOL_GPL(gmap_ipte_notify);
+EXPORT_SYMBOL_GPL(gmap_mprotect_notify);
/**
* ptep_notify - call all invalidation callbacks for a specific pte.
diff --git a/arch/s390/mm/pgtable.c b/arch/s390/mm/pgtable.c
index fa286d0..ab65fb1 100644
--- a/arch/s390/mm/pgtable.c
+++ b/arch/s390/mm/pgtable.c
@@ -179,9 +179,9 @@ static inline pgste_t pgste_set_pte(pte_t *ptep, pgste_t pgste, pte_t entry)
return pgste;
}
-static inline pgste_t pgste_ipte_notify(struct mm_struct *mm,
- unsigned long addr,
- pte_t *ptep, pgste_t pgste)
+static inline pgste_t pgste_pte_notify(struct mm_struct *mm,
+ unsigned long addr,
+ pte_t *ptep, pgste_t pgste)
{
#ifdef CONFIG_PGSTE
if (pgste_val(pgste) & PGSTE_IN_BIT) {
@@ -199,7 +199,7 @@ static inline pgste_t ptep_xchg_start(struct mm_struct *mm,
if (mm_has_pgste(mm)) {
pgste = pgste_get_lock(ptep);
- pgste = pgste_ipte_notify(mm, addr, ptep, pgste);
+ pgste = pgste_pte_notify(mm, addr, ptep, pgste);
}
return pgste;
}
@@ -414,6 +414,50 @@ void ptep_set_notify(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
pgste_set_unlock(ptep, pgste);
}
+/**
+ * ptep_force_prot - change access rights of a locked pte
+ * @mm: pointer to the process mm_struct
+ * @addr: virtual address in the guest address space
+ * @ptep: pointer to the page table entry
+ * @prot: indicates guest access rights: PROT_NONE, PROT_READ or PROT_WRITE
+ *
+ * Returns 0 if the access rights were changed and -EAGAIN if the current
+ * and requested access rights are incompatible.
+ */
+int ptep_force_prot(struct mm_struct *mm, unsigned long addr,
+ pte_t *ptep, int prot)
+{
+ pte_t entry;
+ pgste_t pgste;
+ int pte_i, pte_p;
+
+ pgste = pgste_get_lock(ptep);
+ entry = *ptep;
+ /* Check pte entry after all locks have been acquired */
+ pte_i = pte_val(entry) & _PAGE_INVALID;
+ pte_p = pte_val(entry) & _PAGE_PROTECT;
+ if ((pte_i && (prot != PROT_NONE)) ||
+ (pte_p && (prot & PROT_WRITE))) {
+ pgste_set_unlock(ptep, pgste);
+ return -EAGAIN;
+ }
+ /* Change access rights and set the pgste notification bit */
+ if (prot == PROT_NONE && !pte_i) {
+ ptep_flush_direct(mm, addr, ptep);
+ pgste = pgste_update_all(entry, pgste, mm);
+ pte_val(entry) |= _PAGE_INVALID;
+ }
+ if (prot == PROT_READ && !pte_p) {
+ ptep_flush_direct(mm, addr, ptep);
+ pte_val(entry) &= ~_PAGE_INVALID;
+ pte_val(entry) |= _PAGE_PROTECT;
+ }
+ pgste_val(pgste) |= PGSTE_IN_BIT;
+ pgste = pgste_set_pte(ptep, pgste, entry);
+ pgste_set_unlock(ptep, pgste);
+ return 0;
+}
+
static void ptep_zap_swap_entry(struct mm_struct *mm, swp_entry_t entry)
{
if (!non_swap_entry(entry))
@@ -483,7 +527,7 @@ bool test_and_clear_guest_dirty(struct mm_struct *mm, unsigned long addr)
pgste_val(pgste) &= ~PGSTE_UC_BIT;
pte = *ptep;
if (dirty && (pte_val(pte) & _PAGE_PRESENT)) {
- pgste = pgste_ipte_notify(mm, addr, ptep, pgste);
+ pgste = pgste_pte_notify(mm, addr, ptep, pgste);
__ptep_ipte(addr, ptep);
if (MACHINE_HAS_ESOP || !(pte_val(pte) & _PAGE_WRITE))
pte_val(pte) |= _PAGE_PROTECT;
--
2.5.5
^ permalink raw reply related [flat|nested] 53+ messages in thread* [GIT PULL 04/51] s390/mm: add reference counter to gmap structure
2016-06-21 13:12 [GIT PULL 00/51] KVM: s390: vSIE (nested virtualization) feature for 4.8 (kvm/next) Christian Borntraeger
` (2 preceding siblings ...)
2016-06-21 13:12 ` [GIT PULL 03/51] s390/mm: extended gmap pte notifier Christian Borntraeger
@ 2016-06-21 13:12 ` Christian Borntraeger
2016-06-21 13:12 ` [GIT PULL 05/51] s390/mm: add shadow gmap support Christian Borntraeger
` (47 subsequent siblings)
51 siblings, 0 replies; 53+ messages in thread
From: Christian Borntraeger @ 2016-06-21 13:12 UTC (permalink / raw)
To: Paolo Bonzini, Radim Krčmář
Cc: KVM, Cornelia Huck, linux-s390, Christian Borntraeger,
David Hildenbrand, Martin Schwidefsky
From: Martin Schwidefsky <schwidefsky@de.ibm.com>
Let's use a reference counter mechanism to control the lifetime of
gmap structures. This will be needed for further changes related to
gmap shadows.
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
arch/s390/include/asm/gmap.h | 9 ++++-
arch/s390/kvm/kvm-s390.c | 16 ++++----
arch/s390/mm/gmap.c | 90 ++++++++++++++++++++++++++++++++++----------
3 files changed, 85 insertions(+), 30 deletions(-)
diff --git a/arch/s390/include/asm/gmap.h b/arch/s390/include/asm/gmap.h
index 6897a09..e69853c 100644
--- a/arch/s390/include/asm/gmap.h
+++ b/arch/s390/include/asm/gmap.h
@@ -15,6 +15,7 @@
* @guest_to_host: radix tree with guest to host address translation
* @host_to_guest: radix tree with pointer to segment table entries
* @guest_table_lock: spinlock to protect all entries in the guest page table
+ * @ref_count: reference counter for the gmap structure
* @table: pointer to the page directory
* @asce: address space control element for gmap page table
* @pfault_enabled: defines if pfaults are applicable for the guest
@@ -26,6 +27,7 @@ struct gmap {
struct radix_tree_root guest_to_host;
struct radix_tree_root host_to_guest;
spinlock_t guest_table_lock;
+ atomic_t ref_count;
unsigned long *table;
unsigned long asce;
unsigned long asce_end;
@@ -44,8 +46,11 @@ struct gmap_notifier {
unsigned long end);
};
-struct gmap *gmap_alloc(struct mm_struct *mm, unsigned long limit);
-void gmap_free(struct gmap *gmap);
+struct gmap *gmap_create(struct mm_struct *mm, unsigned long limit);
+void gmap_remove(struct gmap *gmap);
+struct gmap *gmap_get(struct gmap *gmap);
+void gmap_put(struct gmap *gmap);
+
void gmap_enable(struct gmap *gmap);
void gmap_disable(struct gmap *gmap);
int gmap_map_segment(struct gmap *gmap, unsigned long from,
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index b6e7f66..9dd5298 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -532,20 +532,20 @@ static int kvm_s390_set_mem_control(struct kvm *kvm, struct kvm_device_attr *att
if (!new_limit)
return -EINVAL;
- /* gmap_alloc takes last usable address */
+ /* gmap_create takes last usable address */
if (new_limit != KVM_S390_NO_MEM_LIMIT)
new_limit -= 1;
ret = -EBUSY;
mutex_lock(&kvm->lock);
if (!kvm->created_vcpus) {
- /* gmap_alloc will round the limit up */
- struct gmap *new = gmap_alloc(current->mm, new_limit);
+ /* gmap_create will round the limit up */
+ struct gmap *new = gmap_create(current->mm, new_limit);
if (!new) {
ret = -ENOMEM;
} else {
- gmap_free(kvm->arch.gmap);
+ gmap_remove(kvm->arch.gmap);
new->private = kvm;
kvm->arch.gmap = new;
ret = 0;
@@ -1394,7 +1394,7 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
else
kvm->arch.mem_limit = min_t(unsigned long, TASK_MAX_SIZE,
sclp.hamax + 1);
- kvm->arch.gmap = gmap_alloc(current->mm, kvm->arch.mem_limit - 1);
+ kvm->arch.gmap = gmap_create(current->mm, kvm->arch.mem_limit - 1);
if (!kvm->arch.gmap)
goto out_err;
kvm->arch.gmap->private = kvm;
@@ -1427,7 +1427,7 @@ void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
sca_del_vcpu(vcpu);
if (kvm_is_ucontrol(vcpu->kvm))
- gmap_free(vcpu->arch.gmap);
+ gmap_remove(vcpu->arch.gmap);
if (vcpu->kvm->arch.use_cmma)
kvm_s390_vcpu_unsetup_cmma(vcpu);
@@ -1460,7 +1460,7 @@ void kvm_arch_destroy_vm(struct kvm *kvm)
debug_unregister(kvm->arch.dbf);
free_page((unsigned long)kvm->arch.sie_page2);
if (!kvm_is_ucontrol(kvm))
- gmap_free(kvm->arch.gmap);
+ gmap_remove(kvm->arch.gmap);
kvm_s390_destroy_adapters(kvm);
kvm_s390_clear_float_irqs(kvm);
KVM_EVENT(3, "vm 0x%pK destroyed", kvm);
@@ -1469,7 +1469,7 @@ void kvm_arch_destroy_vm(struct kvm *kvm)
/* Section: vcpu related */
static int __kvm_ucontrol_vcpu_init(struct kvm_vcpu *vcpu)
{
- vcpu->arch.gmap = gmap_alloc(current->mm, -1UL);
+ vcpu->arch.gmap = gmap_create(current->mm, -1UL);
if (!vcpu->arch.gmap)
return -ENOMEM;
vcpu->arch.gmap->private = vcpu->kvm;
diff --git a/arch/s390/mm/gmap.c b/arch/s390/mm/gmap.c
index 480c076..fe25f19 100644
--- a/arch/s390/mm/gmap.c
+++ b/arch/s390/mm/gmap.c
@@ -21,13 +21,13 @@
#include <asm/tlb.h>
/**
- * gmap_alloc - allocate a guest address space
+ * gmap_alloc - allocate and initialize a guest address space
* @mm: pointer to the parent mm_struct
* @limit: maximum address of the gmap address space
*
* Returns a guest address space structure.
*/
-struct gmap *gmap_alloc(struct mm_struct *mm, unsigned long limit)
+static struct gmap *gmap_alloc(unsigned long limit)
{
struct gmap *gmap;
struct page *page;
@@ -58,7 +58,7 @@ struct gmap *gmap_alloc(struct mm_struct *mm, unsigned long limit)
INIT_RADIX_TREE(&gmap->guest_to_host, GFP_KERNEL);
INIT_RADIX_TREE(&gmap->host_to_guest, GFP_ATOMIC);
spin_lock_init(&gmap->guest_table_lock);
- gmap->mm = mm;
+ atomic_set(&gmap->ref_count, 1);
page = alloc_pages(GFP_KERNEL, 2);
if (!page)
goto out_free;
@@ -70,9 +70,6 @@ struct gmap *gmap_alloc(struct mm_struct *mm, unsigned long limit)
gmap->asce = atype | _ASCE_TABLE_LENGTH |
_ASCE_USER_BITS | __pa(table);
gmap->asce_end = limit;
- spin_lock(&mm->context.gmap_lock);
- list_add_rcu(&gmap->list, &mm->context.gmap_list);
- spin_unlock(&mm->context.gmap_lock);
return gmap;
out_free:
@@ -80,7 +77,28 @@ out_free:
out:
return NULL;
}
-EXPORT_SYMBOL_GPL(gmap_alloc);
+
+/**
+ * gmap_create - create a guest address space
+ * @mm: pointer to the parent mm_struct
+ * @limit: maximum size of the gmap address space
+ *
+ * Returns a guest address space structure.
+ */
+struct gmap *gmap_create(struct mm_struct *mm, unsigned long limit)
+{
+ struct gmap *gmap;
+
+ gmap = gmap_alloc(limit);
+ if (!gmap)
+ return NULL;
+ gmap->mm = mm;
+ spin_lock(&mm->context.gmap_lock);
+ list_add_rcu(&gmap->list, &mm->context.gmap_list);
+ spin_unlock(&mm->context.gmap_lock);
+ return gmap;
+}
+EXPORT_SYMBOL_GPL(gmap_create);
static void gmap_flush_tlb(struct gmap *gmap)
{
@@ -118,21 +136,10 @@ static void gmap_radix_tree_free(struct radix_tree_root *root)
* gmap_free - free a guest address space
* @gmap: pointer to the guest address space structure
*/
-void gmap_free(struct gmap *gmap)
+static void gmap_free(struct gmap *gmap)
{
struct page *page, *next;
- /* Flush tlb. */
- if (MACHINE_HAS_IDTE)
- __tlb_flush_asce(gmap->mm, gmap->asce);
- else
- __tlb_flush_global();
-
- spin_lock(&gmap->mm->context.gmap_lock);
- list_del_rcu(&gmap->list);
- spin_unlock(&gmap->mm->context.gmap_lock);
- synchronize_rcu();
-
/* Free all segment & region tables. */
list_for_each_entry_safe(page, next, &gmap->crst_list, lru)
__free_pages(page, 2);
@@ -140,7 +147,50 @@ void gmap_free(struct gmap *gmap)
gmap_radix_tree_free(&gmap->host_to_guest);
kfree(gmap);
}
-EXPORT_SYMBOL_GPL(gmap_free);
+
+/**
+ * gmap_get - increase reference counter for guest address space
+ * @gmap: pointer to the guest address space structure
+ *
+ * Returns the gmap pointer
+ */
+struct gmap *gmap_get(struct gmap *gmap)
+{
+ atomic_inc(&gmap->ref_count);
+ return gmap;
+}
+EXPORT_SYMBOL_GPL(gmap_get);
+
+/**
+ * gmap_put - decrease reference counter for guest address space
+ * @gmap: pointer to the guest address space structure
+ *
+ * If the reference counter reaches zero the guest address space is freed.
+ */
+void gmap_put(struct gmap *gmap)
+{
+ if (atomic_dec_return(&gmap->ref_count) == 0)
+ gmap_free(gmap);
+}
+EXPORT_SYMBOL_GPL(gmap_put);
+
+/**
+ * gmap_remove - remove a guest address space but do not free it yet
+ * @gmap: pointer to the guest address space structure
+ */
+void gmap_remove(struct gmap *gmap)
+{
+ /* Flush tlb. */
+ gmap_flush_tlb(gmap);
+ /* Remove gmap from the pre-mm list */
+ spin_lock(&gmap->mm->context.gmap_lock);
+ list_del_rcu(&gmap->list);
+ spin_unlock(&gmap->mm->context.gmap_lock);
+ synchronize_rcu();
+ /* Put reference */
+ gmap_put(gmap);
+}
+EXPORT_SYMBOL_GPL(gmap_remove);
/**
* gmap_enable - switch primary space to the guest address space
--
2.5.5
^ permalink raw reply related [flat|nested] 53+ messages in thread* [GIT PULL 05/51] s390/mm: add shadow gmap support
2016-06-21 13:12 [GIT PULL 00/51] KVM: s390: vSIE (nested virtualization) feature for 4.8 (kvm/next) Christian Borntraeger
` (3 preceding siblings ...)
2016-06-21 13:12 ` [GIT PULL 04/51] s390/mm: add reference counter to gmap structure Christian Borntraeger
@ 2016-06-21 13:12 ` Christian Borntraeger
2016-06-21 13:12 ` [GIT PULL 06/51] s390/mm: add kvm shadow fault function Christian Borntraeger
` (46 subsequent siblings)
51 siblings, 0 replies; 53+ messages in thread
From: Christian Borntraeger @ 2016-06-21 13:12 UTC (permalink / raw)
To: Paolo Bonzini, Radim Krčmář
Cc: KVM, Cornelia Huck, linux-s390, Christian Borntraeger,
David Hildenbrand, Martin Schwidefsky
From: Martin Schwidefsky <schwidefsky@de.ibm.com>
For a nested KVM guest the outer KVM host needs to create shadow
page tables for the nested guest. This patch adds the basic support
to the guest address space (gmap) code.
For each guest address space the inner KVM host creates, the first
outer KVM host needs to create shadow page tables. The address space
is identified by the ASCE loaded into the control register 1 at the
time the inner SIE instruction for the second nested KVM guest is
executed. The outer KVM host creates the shadow tables starting with
the table identified by the ASCE on a on-demand basis. The outer KVM
host will get repeated faults for all the shadow tables needed to
run the second KVM guest.
While a shadow page table for the second KVM guest is active the access
to the origin region, segment and page tables needs to be restricted
for the first KVM guest. For region and segment and page tables the first
KVM guest may read the memory, but write attempt has to lead to an
unshadow. This is done using the page invalid and read-only bits in the
page table of the first KVM guest. If the first guest re-accesses one of
the origin pages of a shadow, it gets a fault and the affected parts of
the shadow page table hierarchy needs to be removed again.
PGSTE tables don't have to be shadowed, as all interpretation assist can't
deal with the invalid bits in the shadow pte being set differently than
the original ones provided by the first KVM guest.
Many bug fixes and improvements by David Hildenbrand.
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
arch/s390/include/asm/gmap.h | 52 +-
arch/s390/include/asm/pgalloc.h | 2 +
arch/s390/include/asm/pgtable.h | 10 +-
arch/s390/include/asm/processor.h | 1 +
arch/s390/mm/fault.c | 1 +
arch/s390/mm/gmap.c | 1168 +++++++++++++++++++++++++++++++++++--
arch/s390/mm/pgalloc.c | 23 +
arch/s390/mm/pgtable.c | 57 +-
8 files changed, 1271 insertions(+), 43 deletions(-)
diff --git a/arch/s390/include/asm/gmap.h b/arch/s390/include/asm/gmap.h
index e69853c..58e65ee 100644
--- a/arch/s390/include/asm/gmap.h
+++ b/arch/s390/include/asm/gmap.h
@@ -10,6 +10,7 @@
/**
* struct gmap_struct - guest address space
+ * @list: list head for the mm->context gmap list
* @crst_list: list of all crst tables used in the guest address space
* @mm: pointer to the parent mm_struct
* @guest_to_host: radix tree with guest to host address translation
@@ -19,6 +20,13 @@
* @table: pointer to the page directory
* @asce: address space control element for gmap page table
* @pfault_enabled: defines if pfaults are applicable for the guest
+ * @host_to_rmap: radix tree with gmap_rmap lists
+ * @children: list of shadow gmap structures
+ * @pt_list: list of all page tables used in the shadow guest address space
+ * @shadow_lock: spinlock to protect the shadow gmap list
+ * @parent: pointer to the parent gmap for shadow guest address spaces
+ * @orig_asce: ASCE for which the shadow page table has been created
+ * @removed: flag to indicate if a shadow guest address space has been removed
*/
struct gmap {
struct list_head list;
@@ -33,9 +41,33 @@ struct gmap {
unsigned long asce_end;
void *private;
bool pfault_enabled;
+ /* Additional data for shadow guest address spaces */
+ struct radix_tree_root host_to_rmap;
+ struct list_head children;
+ struct list_head pt_list;
+ spinlock_t shadow_lock;
+ struct gmap *parent;
+ unsigned long orig_asce;
+ bool removed;
};
/**
+ * struct gmap_rmap - reverse mapping for shadow page table entries
+ * @next: pointer to next rmap in the list
+ * @raddr: virtual rmap address in the shadow guest address space
+ */
+struct gmap_rmap {
+ struct gmap_rmap *next;
+ unsigned long raddr;
+};
+
+#define gmap_for_each_rmap(pos, head) \
+ for (pos = (head); pos; pos = pos->next)
+
+#define gmap_for_each_rmap_safe(pos, n, head) \
+ for (pos = (head); n = pos ? pos->next : NULL, pos; pos = n)
+
+/**
* struct gmap_notifier - notify function block for page invalidation
* @notifier_call: address of callback function
*/
@@ -46,6 +78,11 @@ struct gmap_notifier {
unsigned long end);
};
+static inline int gmap_is_shadow(struct gmap *gmap)
+{
+ return !!gmap->parent;
+}
+
struct gmap *gmap_create(struct mm_struct *mm, unsigned long limit);
void gmap_remove(struct gmap *gmap);
struct gmap *gmap_get(struct gmap *gmap);
@@ -64,9 +101,22 @@ void gmap_discard(struct gmap *, unsigned long from, unsigned long to);
void __gmap_zap(struct gmap *, unsigned long gaddr);
void gmap_unlink(struct mm_struct *, unsigned long *table, unsigned long vmaddr);
+int gmap_read_table(struct gmap *gmap, unsigned long gaddr, unsigned long *val);
+
+struct gmap *gmap_shadow(struct gmap *parent, unsigned long asce);
+int gmap_shadow_r2t(struct gmap *sg, unsigned long saddr, unsigned long r2t);
+int gmap_shadow_r3t(struct gmap *sg, unsigned long saddr, unsigned long r3t);
+int gmap_shadow_sgt(struct gmap *sg, unsigned long saddr, unsigned long sgt);
+int gmap_shadow_pgt(struct gmap *sg, unsigned long saddr, unsigned long pgt);
+int gmap_shadow_pgt_lookup(struct gmap *sg, unsigned long saddr,
+ unsigned long *pgt, int *dat_protection);
+int gmap_shadow_page(struct gmap *sg, unsigned long saddr,
+ unsigned long paddr, int write);
+
void gmap_register_pte_notifier(struct gmap_notifier *);
void gmap_unregister_pte_notifier(struct gmap_notifier *);
-void gmap_pte_notify(struct mm_struct *, unsigned long addr, pte_t *);
+void gmap_pte_notify(struct mm_struct *, unsigned long addr, pte_t *,
+ unsigned long bits);
int gmap_mprotect_notify(struct gmap *, unsigned long start,
unsigned long len, int prot);
diff --git a/arch/s390/include/asm/pgalloc.h b/arch/s390/include/asm/pgalloc.h
index da34cb6..f4eb984 100644
--- a/arch/s390/include/asm/pgalloc.h
+++ b/arch/s390/include/asm/pgalloc.h
@@ -19,8 +19,10 @@ unsigned long *crst_table_alloc(struct mm_struct *);
void crst_table_free(struct mm_struct *, unsigned long *);
unsigned long *page_table_alloc(struct mm_struct *);
+struct page *page_table_alloc_pgste(struct mm_struct *mm);
void page_table_free(struct mm_struct *, unsigned long *);
void page_table_free_rcu(struct mmu_gather *, unsigned long *, unsigned long);
+void page_table_free_pgste(struct page *page);
extern int page_table_allocate_pgste;
static inline void clear_table(unsigned long *s, unsigned long val, size_t n)
diff --git a/arch/s390/include/asm/pgtable.h b/arch/s390/include/asm/pgtable.h
index 35dde6a..a6e7fc8 100644
--- a/arch/s390/include/asm/pgtable.h
+++ b/arch/s390/include/asm/pgtable.h
@@ -256,6 +256,7 @@ static inline int is_module_addr(void *addr)
/* Bits in the region table entry */
#define _REGION_ENTRY_ORIGIN ~0xfffUL/* region/segment table origin */
#define _REGION_ENTRY_PROTECT 0x200 /* region protection bit */
+#define _REGION_ENTRY_OFFSET 0xc0 /* region table offset */
#define _REGION_ENTRY_INVALID 0x20 /* invalid region table entry */
#define _REGION_ENTRY_TYPE_MASK 0x0c /* region/segment table type mask */
#define _REGION_ENTRY_TYPE_R1 0x0c /* region first table type */
@@ -327,6 +328,7 @@ static inline int is_module_addr(void *addr)
#define PGSTE_GC_BIT 0x0002000000000000UL
#define PGSTE_UC_BIT 0x0000800000000000UL /* user dirty (migration) */
#define PGSTE_IN_BIT 0x0000400000000000UL /* IPTE notify bit */
+#define PGSTE_VSIE_BIT 0x0000200000000000UL /* ref'd in a shadow table */
/* Guest Page State used for virtualization */
#define _PGSTE_GPS_ZERO 0x0000000080000000UL
@@ -885,12 +887,16 @@ static inline int ptep_set_access_flags(struct vm_area_struct *vma,
void ptep_set_pte_at(struct mm_struct *mm, unsigned long addr,
pte_t *ptep, pte_t entry);
void ptep_set_notify(struct mm_struct *mm, unsigned long addr, pte_t *ptep);
-void ptep_notify(struct mm_struct *mm, unsigned long addr, pte_t *ptep);
+void ptep_notify(struct mm_struct *mm, unsigned long addr,
+ pte_t *ptep, unsigned long bits);
int ptep_force_prot(struct mm_struct *mm, unsigned long gaddr,
- pte_t *ptep, int prot);
+ pte_t *ptep, int prot, unsigned long bit);
void ptep_zap_unused(struct mm_struct *mm, unsigned long addr,
pte_t *ptep , int reset);
void ptep_zap_key(struct mm_struct *mm, unsigned long addr, pte_t *ptep);
+int ptep_shadow_pte(struct mm_struct *mm, unsigned long saddr,
+ pte_t *sptep, pte_t *tptep, int write);
+void ptep_unshadow_pte(struct mm_struct *mm, unsigned long saddr, pte_t *ptep);
bool test_and_clear_guest_dirty(struct mm_struct *mm, unsigned long address);
int set_guest_storage_key(struct mm_struct *mm, unsigned long addr,
diff --git a/arch/s390/include/asm/processor.h b/arch/s390/include/asm/processor.h
index 9d4d311..94c80b6 100644
--- a/arch/s390/include/asm/processor.h
+++ b/arch/s390/include/asm/processor.h
@@ -109,6 +109,7 @@ struct thread_struct {
unsigned long ksp; /* kernel stack pointer */
mm_segment_t mm_segment;
unsigned long gmap_addr; /* address of last gmap fault. */
+ unsigned int gmap_write_flag; /* gmap fault write indication */
unsigned int gmap_pfault; /* signal of a pending guest pfault */
struct per_regs per_user; /* User specified PER registers */
struct per_event per_event; /* Cause of the last PER trap */
diff --git a/arch/s390/mm/fault.c b/arch/s390/mm/fault.c
index 19288c1..b84416c 100644
--- a/arch/s390/mm/fault.c
+++ b/arch/s390/mm/fault.c
@@ -418,6 +418,7 @@ static inline int do_exception(struct pt_regs *regs, int access)
(struct gmap *) S390_lowcore.gmap : NULL;
if (gmap) {
current->thread.gmap_addr = address;
+ current->thread.gmap_write_flag = !!(flags & FAULT_FLAG_WRITE);
address = __gmap_translate(gmap, address);
if (address == -EFAULT) {
fault = VM_FAULT_BADMAP;
diff --git a/arch/s390/mm/gmap.c b/arch/s390/mm/gmap.c
index fe25f19..6695a09 100644
--- a/arch/s390/mm/gmap.c
+++ b/arch/s390/mm/gmap.c
@@ -55,9 +55,13 @@ static struct gmap *gmap_alloc(unsigned long limit)
if (!gmap)
goto out;
INIT_LIST_HEAD(&gmap->crst_list);
+ INIT_LIST_HEAD(&gmap->children);
+ INIT_LIST_HEAD(&gmap->pt_list);
INIT_RADIX_TREE(&gmap->guest_to_host, GFP_KERNEL);
INIT_RADIX_TREE(&gmap->host_to_guest, GFP_ATOMIC);
+ INIT_RADIX_TREE(&gmap->host_to_rmap, GFP_ATOMIC);
spin_lock_init(&gmap->guest_table_lock);
+ spin_lock_init(&gmap->shadow_lock);
atomic_set(&gmap->ref_count, 1);
page = alloc_pages(GFP_KERNEL, 2);
if (!page)
@@ -132,9 +136,38 @@ static void gmap_radix_tree_free(struct radix_tree_root *root)
} while (nr > 0);
}
+static void gmap_rmap_radix_tree_free(struct radix_tree_root *root)
+{
+ struct gmap_rmap *rmap, *rnext, *head;
+ struct radix_tree_iter iter;
+ unsigned long indices[16];
+ unsigned long index;
+ void **slot;
+ int i, nr;
+
+ /* A radix tree is freed by deleting all of its entries */
+ index = 0;
+ do {
+ nr = 0;
+ radix_tree_for_each_slot(slot, root, &iter, index) {
+ indices[nr] = iter.index;
+ if (++nr == 16)
+ break;
+ }
+ for (i = 0; i < nr; i++) {
+ index = indices[i];
+ head = radix_tree_delete(root, index);
+ gmap_for_each_rmap_safe(rmap, rnext, head)
+ kfree(rmap);
+ }
+ } while (nr > 0);
+}
+
/**
* gmap_free - free a guest address space
* @gmap: pointer to the guest address space structure
+ *
+ * No locks required. There are no references to this gmap anymore.
*/
static void gmap_free(struct gmap *gmap)
{
@@ -145,6 +178,17 @@ static void gmap_free(struct gmap *gmap)
__free_pages(page, 2);
gmap_radix_tree_free(&gmap->guest_to_host);
gmap_radix_tree_free(&gmap->host_to_guest);
+
+ /* Free additional data for a shadow gmap */
+ if (gmap_is_shadow(gmap)) {
+ /* Free all page tables. */
+ list_for_each_entry_safe(page, next, &gmap->pt_list, lru)
+ page_table_free_pgste(page);
+ gmap_rmap_radix_tree_free(&gmap->host_to_rmap);
+ /* Release reference to the parent */
+ gmap_put(gmap->parent);
+ }
+
kfree(gmap);
}
@@ -180,8 +224,20 @@ EXPORT_SYMBOL_GPL(gmap_put);
*/
void gmap_remove(struct gmap *gmap)
{
+ struct gmap *sg, *next;
+
/* Flush tlb. */
gmap_flush_tlb(gmap);
+ /* Remove all shadow gmaps linked to this gmap */
+ if (!list_empty(&gmap->children)) {
+ spin_lock(&gmap->shadow_lock);
+ list_for_each_entry_safe(sg, next, &gmap->children, list) {
+ gmap_flush_tlb(sg);
+ list_del(&sg->list);
+ gmap_put(sg);
+ }
+ spin_unlock(&gmap->shadow_lock);
+ }
/* Remove gmap from the pre-mm list */
spin_lock(&gmap->mm->context.gmap_lock);
list_del_rcu(&gmap->list);
@@ -227,7 +283,7 @@ static int gmap_alloc_table(struct gmap *gmap, unsigned long *table,
return -ENOMEM;
new = (unsigned long *) page_to_phys(page);
crst_table_init(new, init);
- spin_lock(&gmap->mm->page_table_lock);
+ spin_lock(&gmap->guest_table_lock);
if (*table & _REGION_ENTRY_INVALID) {
list_add(&page->lru, &gmap->crst_list);
*table = (unsigned long) new | _REGION_ENTRY_LENGTH |
@@ -235,7 +291,7 @@ static int gmap_alloc_table(struct gmap *gmap, unsigned long *table,
page->index = gaddr;
page = NULL;
}
- spin_unlock(&gmap->mm->page_table_lock);
+ spin_unlock(&gmap->guest_table_lock);
if (page)
__free_pages(page, 2);
return 0;
@@ -271,6 +327,7 @@ static int __gmap_unlink_by_vmaddr(struct gmap *gmap, unsigned long vmaddr)
unsigned long *entry;
int flush = 0;
+ BUG_ON(gmap_is_shadow(gmap));
spin_lock(&gmap->guest_table_lock);
entry = radix_tree_delete(&gmap->host_to_guest, vmaddr >> PMD_SHIFT);
if (entry) {
@@ -310,6 +367,7 @@ int gmap_unmap_segment(struct gmap *gmap, unsigned long to, unsigned long len)
unsigned long off;
int flush;
+ BUG_ON(gmap_is_shadow(gmap));
if ((to | len) & (PMD_SIZE - 1))
return -EINVAL;
if (len == 0 || to + len < to)
@@ -341,6 +399,7 @@ int gmap_map_segment(struct gmap *gmap, unsigned long from,
unsigned long off;
int flush;
+ BUG_ON(gmap_is_shadow(gmap));
if ((from | to | len) & (PMD_SIZE - 1))
return -EINVAL;
if (len == 0 || from + len < from || to + len < to ||
@@ -378,6 +437,8 @@ EXPORT_SYMBOL_GPL(gmap_map_segment);
* This function does not establish potentially missing page table entries.
* The mmap_sem of the mm that belongs to the address space must be held
* when this function gets called.
+ *
+ * Note: Can also be called for shadow gmaps.
*/
unsigned long __gmap_translate(struct gmap *gmap, unsigned long gaddr)
{
@@ -385,6 +446,7 @@ unsigned long __gmap_translate(struct gmap *gmap, unsigned long gaddr)
vmaddr = (unsigned long)
radix_tree_lookup(&gmap->guest_to_host, gaddr >> PMD_SHIFT);
+ /* Note: guest_to_host is empty for a shadow gmap */
return vmaddr ? (vmaddr | (gaddr & ~PMD_MASK)) : -EFAULT;
}
EXPORT_SYMBOL_GPL(__gmap_translate);
@@ -451,6 +513,7 @@ int __gmap_link(struct gmap *gmap, unsigned long gaddr, unsigned long vmaddr)
pmd_t *pmd;
int rc;
+ BUG_ON(gmap_is_shadow(gmap));
/* Create higher level tables in the gmap page table */
table = gmap->table;
if ((gmap->asce & _ASCE_TYPE_MASK) >= _ASCE_TYPE_REGION1) {
@@ -646,36 +709,65 @@ static void gmap_call_notifier(struct gmap *gmap, unsigned long start,
* gmap_table_walk - walk the gmap page tables
* @gmap: pointer to guest mapping meta data structure
* @gaddr: virtual address in the guest address space
+ * @level: page table level to stop at
*
- * Returns a table pointer for the given guest address.
+ * Returns a table entry pointer for the given guest address and @level
+ * @level=0 : returns a pointer to a page table table entry (or NULL)
+ * @level=1 : returns a pointer to a segment table entry (or NULL)
+ * @level=2 : returns a pointer to a region-3 table entry (or NULL)
+ * @level=3 : returns a pointer to a region-2 table entry (or NULL)
+ * @level=4 : returns a pointer to a region-1 table entry (or NULL)
+ *
+ * Returns NULL if the gmap page tables could not be walked to the
+ * requested level.
+ *
+ * Note: Can also be called for shadow gmaps.
*/
static inline unsigned long *gmap_table_walk(struct gmap *gmap,
- unsigned long gaddr)
+ unsigned long gaddr, int level)
{
unsigned long *table;
+ if ((gmap->asce & _ASCE_TYPE_MASK) + 4 < (level * 4))
+ return NULL;
+ if (gmap_is_shadow(gmap) && gmap->removed)
+ return NULL;
+ if (gaddr & (-1UL << (31 + ((gmap->asce & _ASCE_TYPE_MASK) >> 2)*11)))
+ return NULL;
table = gmap->table;
switch (gmap->asce & _ASCE_TYPE_MASK) {
case _ASCE_TYPE_REGION1:
table += (gaddr >> 53) & 0x7ff;
+ if (level == 4)
+ break;
if (*table & _REGION_ENTRY_INVALID)
return NULL;
table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN);
/* Fallthrough */
case _ASCE_TYPE_REGION2:
table += (gaddr >> 42) & 0x7ff;
+ if (level == 3)
+ break;
if (*table & _REGION_ENTRY_INVALID)
return NULL;
table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN);
/* Fallthrough */
case _ASCE_TYPE_REGION3:
table += (gaddr >> 31) & 0x7ff;
+ if (level == 2)
+ break;
if (*table & _REGION_ENTRY_INVALID)
return NULL;
table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN);
/* Fallthrough */
case _ASCE_TYPE_SEGMENT:
table += (gaddr >> 20) & 0x7ff;
+ if (level == 1)
+ break;
+ if (*table & _REGION_ENTRY_INVALID)
+ return NULL;
+ table = (unsigned long *)(*table & _SEGMENT_ENTRY_ORIGIN);
+ table += (gaddr >> 12) & 0xff;
}
return table;
}
@@ -688,16 +780,27 @@ static inline unsigned long *gmap_table_walk(struct gmap *gmap,
* @ptl: pointer to the spinlock pointer
*
* Returns a pointer to the locked pte for a guest address, or NULL
+ *
+ * Note: Can also be called for shadow gmaps.
*/
static pte_t *gmap_pte_op_walk(struct gmap *gmap, unsigned long gaddr,
spinlock_t **ptl)
{
unsigned long *table;
+ if (gmap_is_shadow(gmap))
+ spin_lock(&gmap->guest_table_lock);
/* Walk the gmap page table, lock and get pte pointer */
- table = gmap_table_walk(gmap, gaddr);
- if (!table || *table & _SEGMENT_ENTRY_INVALID)
+ table = gmap_table_walk(gmap, gaddr, 1); /* get segment pointer */
+ if (!table || *table & _SEGMENT_ENTRY_INVALID) {
+ if (gmap_is_shadow(gmap))
+ spin_unlock(&gmap->guest_table_lock);
return NULL;
+ }
+ if (gmap_is_shadow(gmap)) {
+ *ptl = &gmap->guest_table_lock;
+ return pte_offset_map((pmd_t *) table, gaddr);
+ }
return pte_alloc_map_lock(gmap->mm, (pmd_t *) table, gaddr, ptl);
}
@@ -717,6 +820,7 @@ static int gmap_pte_op_fixup(struct gmap *gmap, unsigned long gaddr,
struct mm_struct *mm = gmap->mm;
bool unlocked = false;
+ BUG_ON(gmap_is_shadow(gmap));
if (fixup_user_fault(current, mm, vmaddr, FAULT_FLAG_WRITE, &unlocked))
return -EFAULT;
if (unlocked)
@@ -735,6 +839,51 @@ static void gmap_pte_op_end(spinlock_t *ptl)
spin_unlock(ptl);
}
+/*
+ * gmap_protect_range - remove access rights to memory and set pgste bits
+ * @gmap: pointer to guest mapping meta data structure
+ * @gaddr: virtual address in the guest address space
+ * @len: size of area
+ * @prot: indicates access rights: PROT_NONE, PROT_READ or PROT_WRITE
+ * @bits: pgste notification bits to set
+ *
+ * Returns 0 if successfully protected, -ENOMEM if out of memory and
+ * -EFAULT if gaddr is invalid (or mapping for shadows is missing).
+ *
+ * Called with sg->mm->mmap_sem in read.
+ *
+ * Note: Can also be called for shadow gmaps.
+ */
+static int gmap_protect_range(struct gmap *gmap, unsigned long gaddr,
+ unsigned long len, int prot, unsigned long bits)
+{
+ unsigned long vmaddr;
+ spinlock_t *ptl;
+ pte_t *ptep;
+ int rc;
+
+ while (len) {
+ rc = -EAGAIN;
+ ptep = gmap_pte_op_walk(gmap, gaddr, &ptl);
+ if (ptep) {
+ rc = ptep_force_prot(gmap->mm, gaddr, ptep, prot, bits);
+ gmap_pte_op_end(ptl);
+ }
+ if (rc) {
+ vmaddr = __gmap_translate(gmap, gaddr);
+ if (IS_ERR_VALUE(vmaddr))
+ return vmaddr;
+ rc = gmap_pte_op_fixup(gmap, gaddr, vmaddr);
+ if (rc)
+ return rc;
+ continue;
+ }
+ gaddr += PAGE_SIZE;
+ len -= PAGE_SIZE;
+ }
+ return 0;
+}
+
/**
* gmap_mprotect_notify - change access rights for a range of ptes and
* call the notifier if any pte changes again
@@ -752,61 +901,1012 @@ static void gmap_pte_op_end(spinlock_t *ptl)
int gmap_mprotect_notify(struct gmap *gmap, unsigned long gaddr,
unsigned long len, int prot)
{
- unsigned long vmaddr;
- spinlock_t *ptl;
- pte_t *ptep;
- int rc = 0;
+ int rc;
- if ((gaddr & ~PAGE_MASK) || (len & ~PAGE_MASK))
+ if ((gaddr & ~PAGE_MASK) || (len & ~PAGE_MASK) || gmap_is_shadow(gmap))
return -EINVAL;
if (!MACHINE_HAS_ESOP && prot == PROT_READ)
return -EINVAL;
down_read(&gmap->mm->mmap_sem);
- while (len) {
- rc = -EAGAIN;
- ptep = gmap_pte_op_walk(gmap, gaddr, &ptl);
- if (ptep) {
- rc = ptep_force_prot(gmap->mm, gaddr, ptep, prot);
- gmap_pte_op_end(ptl);
- }
- if (rc) {
- vmaddr = __gmap_translate(gmap, gaddr);
- if (IS_ERR_VALUE(vmaddr)) {
- rc = vmaddr;
- break;
- }
- rc = gmap_pte_op_fixup(gmap, gaddr, vmaddr);
- if (rc)
- break;
- continue;
- }
- gaddr += PAGE_SIZE;
- len -= PAGE_SIZE;
- }
+ rc = gmap_protect_range(gmap, gaddr, len, prot, PGSTE_IN_BIT);
up_read(&gmap->mm->mmap_sem);
return rc;
}
EXPORT_SYMBOL_GPL(gmap_mprotect_notify);
/**
+ * gmap_read_table - get an unsigned long value from a guest page table using
+ * absolute addressing, without marking the page referenced.
+ * @gmap: pointer to guest mapping meta data structure
+ * @gaddr: virtual address in the guest address space
+ * @val: pointer to the unsigned long value to return
+ *
+ * Returns 0 if the value was read, -ENOMEM if out of memory and -EFAULT
+ * if reading using the virtual address failed.
+ *
+ * Called with gmap->mm->mmap_sem in read.
+ */
+int gmap_read_table(struct gmap *gmap, unsigned long gaddr, unsigned long *val)
+{
+ unsigned long address, vmaddr;
+ spinlock_t *ptl;
+ pte_t *ptep, pte;
+ int rc;
+
+ while (1) {
+ rc = -EAGAIN;
+ ptep = gmap_pte_op_walk(gmap, gaddr, &ptl);
+ if (ptep) {
+ pte = *ptep;
+ if (pte_present(pte) && (pte_val(pte) & _PAGE_READ)) {
+ address = pte_val(pte) & PAGE_MASK;
+ address += gaddr & ~PAGE_MASK;
+ *val = *(unsigned long *) address;
+ pte_val(*ptep) |= _PAGE_YOUNG;
+ /* Do *NOT* clear the _PAGE_INVALID bit! */
+ rc = 0;
+ }
+ gmap_pte_op_end(ptl);
+ }
+ if (!rc)
+ break;
+ vmaddr = __gmap_translate(gmap, gaddr);
+ if (IS_ERR_VALUE(vmaddr)) {
+ rc = vmaddr;
+ break;
+ }
+ rc = gmap_pte_op_fixup(gmap, gaddr, vmaddr);
+ if (rc)
+ break;
+ }
+ return rc;
+}
+EXPORT_SYMBOL_GPL(gmap_read_table);
+
+/**
+ * gmap_insert_rmap - add a rmap to the host_to_rmap radix tree
+ * @sg: pointer to the shadow guest address space structure
+ * @vmaddr: vm address associated with the rmap
+ * @rmap: pointer to the rmap structure
+ *
+ * Called with the sg->guest_table_lock
+ */
+static inline void gmap_insert_rmap(struct gmap *sg, unsigned long vmaddr,
+ struct gmap_rmap *rmap)
+{
+ void **slot;
+
+ BUG_ON(!gmap_is_shadow(sg));
+ slot = radix_tree_lookup_slot(&sg->host_to_rmap, vmaddr >> PAGE_SHIFT);
+ if (slot) {
+ rmap->next = radix_tree_deref_slot_protected(slot,
+ &sg->guest_table_lock);
+ radix_tree_replace_slot(slot, rmap);
+ } else {
+ rmap->next = NULL;
+ radix_tree_insert(&sg->host_to_rmap, vmaddr >> PAGE_SHIFT,
+ rmap);
+ }
+}
+
+/**
+ * gmap_protect_rmap - modify access rights to memory and create an rmap
+ * @sg: pointer to the shadow guest address space structure
+ * @raddr: rmap address in the shadow gmap
+ * @paddr: address in the parent guest address space
+ * @len: length of the memory area to protect
+ * @prot: indicates access rights: none, read-only or read-write
+ *
+ * Returns 0 if successfully protected and the rmap was created, -ENOMEM
+ * if out of memory and -EFAULT if paddr is invalid.
+ */
+static int gmap_protect_rmap(struct gmap *sg, unsigned long raddr,
+ unsigned long paddr, unsigned long len, int prot)
+{
+ struct gmap *parent;
+ struct gmap_rmap *rmap;
+ unsigned long vmaddr;
+ spinlock_t *ptl;
+ pte_t *ptep;
+ int rc;
+
+ BUG_ON(!gmap_is_shadow(sg));
+ parent = sg->parent;
+ while (len) {
+ vmaddr = __gmap_translate(parent, paddr);
+ if (IS_ERR_VALUE(vmaddr))
+ return vmaddr;
+ rmap = kzalloc(sizeof(*rmap), GFP_KERNEL);
+ if (!rmap)
+ return -ENOMEM;
+ rmap->raddr = raddr;
+ rc = radix_tree_preload(GFP_KERNEL);
+ if (rc) {
+ kfree(rmap);
+ return rc;
+ }
+ rc = -EAGAIN;
+ ptep = gmap_pte_op_walk(parent, paddr, &ptl);
+ if (ptep) {
+ spin_lock(&sg->guest_table_lock);
+ rc = ptep_force_prot(parent->mm, paddr, ptep, prot,
+ PGSTE_VSIE_BIT);
+ if (!rc)
+ gmap_insert_rmap(sg, vmaddr, rmap);
+ spin_unlock(&sg->guest_table_lock);
+ gmap_pte_op_end(ptl);
+ }
+ radix_tree_preload_end();
+ if (rc) {
+ kfree(rmap);
+ rc = gmap_pte_op_fixup(parent, paddr, vmaddr);
+ if (rc)
+ return rc;
+ continue;
+ }
+ paddr += PAGE_SIZE;
+ len -= PAGE_SIZE;
+ }
+ return 0;
+}
+
+#define _SHADOW_RMAP_MASK 0x7
+#define _SHADOW_RMAP_REGION1 0x5
+#define _SHADOW_RMAP_REGION2 0x4
+#define _SHADOW_RMAP_REGION3 0x3
+#define _SHADOW_RMAP_SEGMENT 0x2
+#define _SHADOW_RMAP_PGTABLE 0x1
+
+/**
+ * gmap_idte_one - invalidate a single region or segment table entry
+ * @asce: region or segment table *origin* + table-type bits
+ * @vaddr: virtual address to identify the table entry to flush
+ *
+ * The invalid bit of a single region or segment table entry is set
+ * and the associated TLB entries depending on the entry are flushed.
+ * The table-type of the @asce identifies the portion of the @vaddr
+ * that is used as the invalidation index.
+ */
+static inline void gmap_idte_one(unsigned long asce, unsigned long vaddr)
+{
+ asm volatile(
+ " .insn rrf,0xb98e0000,%0,%1,0,0"
+ : : "a" (asce), "a" (vaddr) : "cc", "memory");
+}
+
+/**
+ * gmap_unshadow_page - remove a page from a shadow page table
+ * @sg: pointer to the shadow guest address space structure
+ * @raddr: rmap address in the shadow guest address space
+ *
+ * Called with the sg->guest_table_lock
+ */
+static void gmap_unshadow_page(struct gmap *sg, unsigned long raddr)
+{
+ unsigned long *table;
+
+ BUG_ON(!gmap_is_shadow(sg));
+ table = gmap_table_walk(sg, raddr, 0); /* get page table pointer */
+ if (!table || *table & _PAGE_INVALID)
+ return;
+ gmap_call_notifier(sg, raddr, raddr + (1UL << 12) - 1);
+ ptep_unshadow_pte(sg->mm, raddr, (pte_t *) table);
+}
+
+/**
+ * __gmap_unshadow_pgt - remove all entries from a shadow page table
+ * @sg: pointer to the shadow guest address space structure
+ * @raddr: rmap address in the shadow guest address space
+ * @pgt: pointer to the start of a shadow page table
+ *
+ * Called with the sg->guest_table_lock
+ */
+static void __gmap_unshadow_pgt(struct gmap *sg, unsigned long raddr,
+ unsigned long *pgt)
+{
+ int i;
+
+ BUG_ON(!gmap_is_shadow(sg));
+ for (i = 0; i < 256; i++, raddr += 1UL << 12)
+ pgt[i] = _PAGE_INVALID;
+}
+
+/**
+ * gmap_unshadow_pgt - remove a shadow page table from a segment entry
+ * @sg: pointer to the shadow guest address space structure
+ * @raddr: address in the shadow guest address space
+ *
+ * Called with the sg->guest_table_lock
+ */
+static void gmap_unshadow_pgt(struct gmap *sg, unsigned long raddr)
+{
+ unsigned long sto, *ste, *pgt;
+ struct page *page;
+
+ BUG_ON(!gmap_is_shadow(sg));
+ ste = gmap_table_walk(sg, raddr, 1); /* get segment pointer */
+ if (!ste || *ste & _SEGMENT_ENTRY_INVALID)
+ return;
+ gmap_call_notifier(sg, raddr, raddr + (1UL << 20) - 1);
+ sto = (unsigned long) (ste - ((raddr >> 20) & 0x7ff));
+ gmap_idte_one(sto | _ASCE_TYPE_SEGMENT, raddr);
+ pgt = (unsigned long *)(*ste & _SEGMENT_ENTRY_ORIGIN);
+ *ste = _SEGMENT_ENTRY_EMPTY;
+ __gmap_unshadow_pgt(sg, raddr, pgt);
+ /* Free page table */
+ page = pfn_to_page(__pa(pgt) >> PAGE_SHIFT);
+ list_del(&page->lru);
+ page_table_free_pgste(page);
+}
+
+/**
+ * __gmap_unshadow_sgt - remove all entries from a shadow segment table
+ * @sg: pointer to the shadow guest address space structure
+ * @raddr: rmap address in the shadow guest address space
+ * @sgt: pointer to the start of a shadow segment table
+ *
+ * Called with the sg->guest_table_lock
+ */
+static void __gmap_unshadow_sgt(struct gmap *sg, unsigned long raddr,
+ unsigned long *sgt)
+{
+ unsigned long asce, *pgt;
+ struct page *page;
+ int i;
+
+ BUG_ON(!gmap_is_shadow(sg));
+ asce = (unsigned long) sgt | _ASCE_TYPE_SEGMENT;
+ for (i = 0; i < 2048; i++, raddr += 1UL << 20) {
+ if (sgt[i] & _SEGMENT_ENTRY_INVALID)
+ continue;
+ pgt = (unsigned long *)(sgt[i] & _REGION_ENTRY_ORIGIN);
+ sgt[i] = _SEGMENT_ENTRY_EMPTY;
+ __gmap_unshadow_pgt(sg, raddr, pgt);
+ /* Free page table */
+ page = pfn_to_page(__pa(pgt) >> PAGE_SHIFT);
+ list_del(&page->lru);
+ page_table_free_pgste(page);
+ }
+}
+
+/**
+ * gmap_unshadow_sgt - remove a shadow segment table from a region-3 entry
+ * @sg: pointer to the shadow guest address space structure
+ * @raddr: rmap address in the shadow guest address space
+ *
+ * Called with the shadow->guest_table_lock
+ */
+static void gmap_unshadow_sgt(struct gmap *sg, unsigned long raddr)
+{
+ unsigned long r3o, *r3e, *sgt;
+ struct page *page;
+
+ BUG_ON(!gmap_is_shadow(sg));
+ r3e = gmap_table_walk(sg, raddr, 2); /* get region-3 pointer */
+ if (!r3e || *r3e & _REGION_ENTRY_INVALID)
+ return;
+ gmap_call_notifier(sg, raddr, raddr + (1UL << 31) - 1);
+ r3o = (unsigned long) (r3e - ((raddr >> 31) & 0x7ff));
+ gmap_idte_one(r3o | _ASCE_TYPE_REGION3, raddr);
+ sgt = (unsigned long *)(*r3e & _REGION_ENTRY_ORIGIN);
+ *r3e = _REGION3_ENTRY_EMPTY;
+ __gmap_unshadow_sgt(sg, raddr, sgt);
+ /* Free segment table */
+ page = pfn_to_page(__pa(sgt) >> PAGE_SHIFT);
+ list_del(&page->lru);
+ __free_pages(page, 2);
+}
+
+/**
+ * __gmap_unshadow_r3t - remove all entries from a shadow region-3 table
+ * @sg: pointer to the shadow guest address space structure
+ * @raddr: address in the shadow guest address space
+ * @r3t: pointer to the start of a shadow region-3 table
+ *
+ * Called with the sg->guest_table_lock
+ */
+static void __gmap_unshadow_r3t(struct gmap *sg, unsigned long raddr,
+ unsigned long *r3t)
+{
+ unsigned long asce, *sgt;
+ struct page *page;
+ int i;
+
+ BUG_ON(!gmap_is_shadow(sg));
+ asce = (unsigned long) r3t | _ASCE_TYPE_REGION3;
+ for (i = 0; i < 2048; i++, raddr += 1UL << 31) {
+ if (r3t[i] & _REGION_ENTRY_INVALID)
+ continue;
+ sgt = (unsigned long *)(r3t[i] & _REGION_ENTRY_ORIGIN);
+ r3t[i] = _REGION3_ENTRY_EMPTY;
+ __gmap_unshadow_sgt(sg, raddr, sgt);
+ /* Free segment table */
+ page = pfn_to_page(__pa(sgt) >> PAGE_SHIFT);
+ list_del(&page->lru);
+ __free_pages(page, 2);
+ }
+}
+
+/**
+ * gmap_unshadow_r3t - remove a shadow region-3 table from a region-2 entry
+ * @sg: pointer to the shadow guest address space structure
+ * @raddr: rmap address in the shadow guest address space
+ *
+ * Called with the sg->guest_table_lock
+ */
+static void gmap_unshadow_r3t(struct gmap *sg, unsigned long raddr)
+{
+ unsigned long r2o, *r2e, *r3t;
+ struct page *page;
+
+ BUG_ON(!gmap_is_shadow(sg));
+ r2e = gmap_table_walk(sg, raddr, 3); /* get region-2 pointer */
+ if (!r2e || *r2e & _REGION_ENTRY_INVALID)
+ return;
+ gmap_call_notifier(sg, raddr, raddr + (1UL << 42) - 1);
+ r2o = (unsigned long) (r2e - ((raddr >> 42) & 0x7ff));
+ gmap_idte_one(r2o | _ASCE_TYPE_REGION2, raddr);
+ r3t = (unsigned long *)(*r2e & _REGION_ENTRY_ORIGIN);
+ *r2e = _REGION2_ENTRY_EMPTY;
+ __gmap_unshadow_r3t(sg, raddr, r3t);
+ /* Free region 3 table */
+ page = pfn_to_page(__pa(r3t) >> PAGE_SHIFT);
+ list_del(&page->lru);
+ __free_pages(page, 2);
+}
+
+/**
+ * __gmap_unshadow_r2t - remove all entries from a shadow region-2 table
+ * @sg: pointer to the shadow guest address space structure
+ * @raddr: rmap address in the shadow guest address space
+ * @r2t: pointer to the start of a shadow region-2 table
+ *
+ * Called with the sg->guest_table_lock
+ */
+static void __gmap_unshadow_r2t(struct gmap *sg, unsigned long raddr,
+ unsigned long *r2t)
+{
+ unsigned long asce, *r3t;
+ struct page *page;
+ int i;
+
+ BUG_ON(!gmap_is_shadow(sg));
+ asce = (unsigned long) r2t | _ASCE_TYPE_REGION2;
+ for (i = 0; i < 2048; i++, raddr += 1UL << 42) {
+ if (r2t[i] & _REGION_ENTRY_INVALID)
+ continue;
+ r3t = (unsigned long *)(r2t[i] & _REGION_ENTRY_ORIGIN);
+ r2t[i] = _REGION2_ENTRY_EMPTY;
+ __gmap_unshadow_r3t(sg, raddr, r3t);
+ /* Free region 3 table */
+ page = pfn_to_page(__pa(r3t) >> PAGE_SHIFT);
+ list_del(&page->lru);
+ __free_pages(page, 2);
+ }
+}
+
+/**
+ * gmap_unshadow_r2t - remove a shadow region-2 table from a region-1 entry
+ * @sg: pointer to the shadow guest address space structure
+ * @raddr: rmap address in the shadow guest address space
+ *
+ * Called with the sg->guest_table_lock
+ */
+static void gmap_unshadow_r2t(struct gmap *sg, unsigned long raddr)
+{
+ unsigned long r1o, *r1e, *r2t;
+ struct page *page;
+
+ BUG_ON(!gmap_is_shadow(sg));
+ r1e = gmap_table_walk(sg, raddr, 4); /* get region-1 pointer */
+ if (!r1e || *r1e & _REGION_ENTRY_INVALID)
+ return;
+ gmap_call_notifier(sg, raddr, raddr + (1UL << 53) - 1);
+ r1o = (unsigned long) (r1e - ((raddr >> 53) & 0x7ff));
+ gmap_idte_one(r1o | _ASCE_TYPE_REGION1, raddr);
+ r2t = (unsigned long *)(*r1e & _REGION_ENTRY_ORIGIN);
+ *r1e = _REGION1_ENTRY_EMPTY;
+ __gmap_unshadow_r2t(sg, raddr, r2t);
+ /* Free region 2 table */
+ page = pfn_to_page(__pa(r2t) >> PAGE_SHIFT);
+ list_del(&page->lru);
+ __free_pages(page, 2);
+}
+
+/**
+ * __gmap_unshadow_r1t - remove all entries from a shadow region-1 table
+ * @sg: pointer to the shadow guest address space structure
+ * @raddr: rmap address in the shadow guest address space
+ * @r1t: pointer to the start of a shadow region-1 table
+ *
+ * Called with the shadow->guest_table_lock
+ */
+static void __gmap_unshadow_r1t(struct gmap *sg, unsigned long raddr,
+ unsigned long *r1t)
+{
+ unsigned long asce, *r2t;
+ struct page *page;
+ int i;
+
+ BUG_ON(!gmap_is_shadow(sg));
+ asce = (unsigned long) r1t | _ASCE_TYPE_REGION1;
+ for (i = 0; i < 2048; i++, raddr += 1UL << 53) {
+ if (r1t[i] & _REGION_ENTRY_INVALID)
+ continue;
+ r2t = (unsigned long *)(r1t[i] & _REGION_ENTRY_ORIGIN);
+ __gmap_unshadow_r2t(sg, raddr, r2t);
+ /* Clear entry and flush translation r1t -> r2t */
+ gmap_idte_one(asce, raddr);
+ r1t[i] = _REGION1_ENTRY_EMPTY;
+ /* Free region 2 table */
+ page = pfn_to_page(__pa(r2t) >> PAGE_SHIFT);
+ list_del(&page->lru);
+ __free_pages(page, 2);
+ }
+}
+
+/**
+ * gmap_unshadow - remove a shadow page table completely
+ * @sg: pointer to the shadow guest address space structure
+ *
+ * Called with sg->guest_table_lock
+ */
+static void gmap_unshadow(struct gmap *sg)
+{
+ unsigned long *table;
+
+ BUG_ON(!gmap_is_shadow(sg));
+ if (sg->removed)
+ return;
+ sg->removed = 1;
+ gmap_call_notifier(sg, 0, -1UL);
+ table = (unsigned long *)(sg->asce & _ASCE_ORIGIN);
+ switch (sg->asce & _ASCE_TYPE_MASK) {
+ case _ASCE_TYPE_REGION1:
+ __gmap_unshadow_r1t(sg, 0, table);
+ break;
+ case _ASCE_TYPE_REGION2:
+ __gmap_unshadow_r2t(sg, 0, table);
+ break;
+ case _ASCE_TYPE_REGION3:
+ __gmap_unshadow_r3t(sg, 0, table);
+ break;
+ case _ASCE_TYPE_SEGMENT:
+ __gmap_unshadow_sgt(sg, 0, table);
+ break;
+ }
+}
+
+/**
+ * gmap_find_shadow - find a specific asce in the list of shadow tables
+ * @parent: pointer to the parent gmap
+ * @asce: ASCE for which the shadow table is created
+ *
+ * Returns the pointer to a gmap if a shadow table with the given asce is
+ * already available, otherwise NULL
+ */
+static struct gmap *gmap_find_shadow(struct gmap *parent, unsigned long asce)
+{
+ struct gmap *sg;
+
+ list_for_each_entry(sg, &parent->children, list) {
+ if (sg->orig_asce != asce || sg->removed)
+ continue;
+ atomic_inc(&sg->ref_count);
+ return sg;
+ }
+ return NULL;
+}
+
+/**
+ * gmap_shadow - create/find a shadow guest address space
+ * @parent: pointer to the parent gmap
+ * @asce: ASCE for which the shadow table is created
+ *
+ * The pages of the top level page table referred by the asce parameter
+ * will be set to read-only and marked in the PGSTEs of the kvm process.
+ * The shadow table will be removed automatically on any change to the
+ * PTE mapping for the source table.
+ *
+ * Returns a guest address space structure, NULL if out of memory or if
+ * anything goes wrong while protecting the top level pages.
+ */
+struct gmap *gmap_shadow(struct gmap *parent, unsigned long asce)
+{
+ struct gmap *sg, *new;
+ unsigned long limit;
+ int rc;
+
+ BUG_ON(gmap_is_shadow(parent));
+ spin_lock(&parent->shadow_lock);
+ sg = gmap_find_shadow(parent, asce);
+ spin_unlock(&parent->shadow_lock);
+ if (sg)
+ return sg;
+ /* Create a new shadow gmap */
+ limit = -1UL >> (33 - (((asce & _ASCE_TYPE_MASK) >> 2) * 11));
+ new = gmap_alloc(limit);
+ if (!new)
+ return NULL;
+ new->mm = parent->mm;
+ new->parent = gmap_get(parent);
+ new->orig_asce = asce;
+ down_read(&parent->mm->mmap_sem);
+ rc = gmap_protect_range(parent, asce & _ASCE_ORIGIN,
+ ((asce & _ASCE_TABLE_LENGTH) + 1) * 4096,
+ PROT_READ, PGSTE_VSIE_BIT);
+ up_read(&parent->mm->mmap_sem);
+ if (rc) {
+ atomic_set(&new->ref_count, 2);
+ spin_lock(&parent->shadow_lock);
+ /* Recheck if another CPU created the same shadow */
+ sg = gmap_find_shadow(parent, asce);
+ if (!sg) {
+ list_add(&new->list, &parent->children);
+ sg = new;
+ new = NULL;
+ }
+ spin_unlock(&parent->shadow_lock);
+ }
+ if (new)
+ gmap_free(new);
+ return sg;
+}
+EXPORT_SYMBOL_GPL(gmap_shadow);
+
+/**
+ * gmap_shadow_r2t - create an empty shadow region 2 table
+ * @sg: pointer to the shadow guest address space structure
+ * @saddr: faulting address in the shadow gmap
+ * @r2t: parent gmap address of the region 2 table to get shadowed
+ *
+ * The r2t parameter specifies the address of the source table. The
+ * four pages of the source table are made read-only in the parent gmap
+ * address space. A write to the source table area @r2t will automatically
+ * remove the shadow r2 table and all of its decendents.
+ *
+ * Returns 0 if successfully shadowed or already shadowed, -EAGAIN if the
+ * shadow table structure is incomplete, -ENOMEM if out of memory and
+ * -EFAULT if an address in the parent gmap could not be resolved.
+ *
+ * Called with sg->mm->mmap_sem in read.
+ */
+int gmap_shadow_r2t(struct gmap *sg, unsigned long saddr, unsigned long r2t)
+{
+ unsigned long raddr, origin, offset, len;
+ unsigned long *s_r2t, *table;
+ struct page *page;
+ int rc;
+
+ BUG_ON(!gmap_is_shadow(sg));
+ /* Allocate a shadow region second table */
+ page = alloc_pages(GFP_KERNEL, 2);
+ if (!page)
+ return -ENOMEM;
+ page->index = r2t & _REGION_ENTRY_ORIGIN;
+ s_r2t = (unsigned long *) page_to_phys(page);
+ /* Install shadow region second table */
+ spin_lock(&sg->guest_table_lock);
+ table = gmap_table_walk(sg, saddr, 4); /* get region-1 pointer */
+ if (!table) {
+ rc = -EAGAIN; /* Race with unshadow */
+ goto out_free;
+ }
+ if (!(*table & _REGION_ENTRY_INVALID)) {
+ rc = 0; /* Already established */
+ goto out_free;
+ }
+ crst_table_init(s_r2t, _REGION2_ENTRY_EMPTY);
+ *table = (unsigned long) s_r2t |
+ _REGION_ENTRY_LENGTH | _REGION_ENTRY_TYPE_R1;
+ list_add(&page->lru, &sg->crst_list);
+ spin_unlock(&sg->guest_table_lock);
+ /* Make r2t read-only in parent gmap page table */
+ raddr = (saddr & 0xffe0000000000000UL) | _SHADOW_RMAP_REGION1;
+ origin = r2t & _REGION_ENTRY_ORIGIN;
+ offset = ((r2t & _REGION_ENTRY_OFFSET) >> 6) * 4096;
+ len = ((r2t & _REGION_ENTRY_LENGTH) + 1) * 4096 - offset;
+ rc = gmap_protect_rmap(sg, raddr, origin + offset, len, PROT_READ);
+ if (rc) {
+ spin_lock(&sg->guest_table_lock);
+ gmap_unshadow_r2t(sg, raddr);
+ spin_unlock(&sg->guest_table_lock);
+ }
+ return rc;
+out_free:
+ spin_unlock(&sg->guest_table_lock);
+ __free_pages(page, 2);
+ return rc;
+}
+EXPORT_SYMBOL_GPL(gmap_shadow_r2t);
+
+/**
+ * gmap_shadow_r3t - create a shadow region 3 table
+ * @sg: pointer to the shadow guest address space structure
+ * @saddr: faulting address in the shadow gmap
+ * @r3t: parent gmap address of the region 3 table to get shadowed
+ *
+ * Returns 0 if successfully shadowed or already shadowed, -EAGAIN if the
+ * shadow table structure is incomplete, -ENOMEM if out of memory and
+ * -EFAULT if an address in the parent gmap could not be resolved.
+ *
+ * Called with sg->mm->mmap_sem in read.
+ */
+int gmap_shadow_r3t(struct gmap *sg, unsigned long saddr, unsigned long r3t)
+{
+ unsigned long raddr, origin, offset, len;
+ unsigned long *s_r3t, *table;
+ struct page *page;
+ int rc;
+
+ BUG_ON(!gmap_is_shadow(sg));
+ /* Allocate a shadow region second table */
+ page = alloc_pages(GFP_KERNEL, 2);
+ if (!page)
+ return -ENOMEM;
+ page->index = r3t & _REGION_ENTRY_ORIGIN;
+ s_r3t = (unsigned long *) page_to_phys(page);
+ /* Install shadow region second table */
+ spin_lock(&sg->guest_table_lock);
+ table = gmap_table_walk(sg, saddr, 3); /* get region-2 pointer */
+ if (!table) {
+ rc = -EAGAIN; /* Race with unshadow */
+ goto out_free;
+ }
+ if (!(*table & _REGION_ENTRY_INVALID)) {
+ rc = 0; /* Already established */
+ goto out_free;
+ }
+ crst_table_init(s_r3t, _REGION3_ENTRY_EMPTY);
+ *table = (unsigned long) s_r3t |
+ _REGION_ENTRY_LENGTH | _REGION_ENTRY_TYPE_R2;
+ list_add(&page->lru, &sg->crst_list);
+ spin_unlock(&sg->guest_table_lock);
+ /* Make r3t read-only in parent gmap page table */
+ raddr = (saddr & 0xfffffc0000000000UL) | _SHADOW_RMAP_REGION2;
+ origin = r3t & _REGION_ENTRY_ORIGIN;
+ offset = ((r3t & _REGION_ENTRY_OFFSET) >> 6) * 4096;
+ len = ((r3t & _REGION_ENTRY_LENGTH) + 1) * 4096 - offset;
+ rc = gmap_protect_rmap(sg, raddr, origin + offset, len, PROT_READ);
+ if (rc) {
+ spin_lock(&sg->guest_table_lock);
+ gmap_unshadow_r3t(sg, raddr);
+ spin_unlock(&sg->guest_table_lock);
+ }
+ return rc;
+out_free:
+ spin_unlock(&sg->guest_table_lock);
+ __free_pages(page, 2);
+ return rc;
+}
+EXPORT_SYMBOL_GPL(gmap_shadow_r3t);
+
+/**
+ * gmap_shadow_sgt - create a shadow segment table
+ * @sg: pointer to the shadow guest address space structure
+ * @saddr: faulting address in the shadow gmap
+ * @sgt: parent gmap address of the segment table to get shadowed
+ *
+ * Returns: 0 if successfully shadowed or already shadowed, -EAGAIN if the
+ * shadow table structure is incomplete, -ENOMEM if out of memory and
+ * -EFAULT if an address in the parent gmap could not be resolved.
+ *
+ * Called with sg->mm->mmap_sem in read.
+ */
+int gmap_shadow_sgt(struct gmap *sg, unsigned long saddr, unsigned long sgt)
+{
+ unsigned long raddr, origin, offset, len;
+ unsigned long *s_sgt, *table;
+ struct page *page;
+ int rc;
+
+ BUG_ON(!gmap_is_shadow(sg));
+ /* Allocate a shadow segment table */
+ page = alloc_pages(GFP_KERNEL, 2);
+ if (!page)
+ return -ENOMEM;
+ page->index = sgt & _REGION_ENTRY_ORIGIN;
+ s_sgt = (unsigned long *) page_to_phys(page);
+ /* Install shadow region second table */
+ spin_lock(&sg->guest_table_lock);
+ table = gmap_table_walk(sg, saddr, 2); /* get region-3 pointer */
+ if (!table) {
+ rc = -EAGAIN; /* Race with unshadow */
+ goto out_free;
+ }
+ if (!(*table & _REGION_ENTRY_INVALID)) {
+ rc = 0; /* Already established */
+ goto out_free;
+ }
+ crst_table_init(s_sgt, _SEGMENT_ENTRY_EMPTY);
+ *table = (unsigned long) s_sgt |
+ _REGION_ENTRY_LENGTH | _REGION_ENTRY_TYPE_R3;
+ list_add(&page->lru, &sg->crst_list);
+ spin_unlock(&sg->guest_table_lock);
+ /* Make sgt read-only in parent gmap page table */
+ raddr = (saddr & 0xffffffff80000000UL) | _SHADOW_RMAP_REGION3;
+ origin = sgt & _REGION_ENTRY_ORIGIN;
+ offset = ((sgt & _REGION_ENTRY_OFFSET) >> 6) * 4096;
+ len = ((sgt & _REGION_ENTRY_LENGTH) + 1) * 4096 - offset;
+ rc = gmap_protect_rmap(sg, raddr, origin + offset, len, PROT_READ);
+ if (rc) {
+ spin_lock(&sg->guest_table_lock);
+ gmap_unshadow_sgt(sg, raddr);
+ spin_unlock(&sg->guest_table_lock);
+ }
+ return rc;
+out_free:
+ spin_unlock(&sg->guest_table_lock);
+ __free_pages(page, 2);
+ return rc;
+}
+EXPORT_SYMBOL_GPL(gmap_shadow_sgt);
+
+/**
+ * gmap_shadow_lookup_pgtable - find a shadow page table
+ * @sg: pointer to the shadow guest address space structure
+ * @saddr: the address in the shadow aguest address space
+ * @pgt: parent gmap address of the page table to get shadowed
+ * @dat_protection: if the pgtable is marked as protected by dat
+ *
+ * Returns 0 if the shadow page table was found and -EAGAIN if the page
+ * table was not found.
+ *
+ * Called with sg->mm->mmap_sem in read.
+ */
+int gmap_shadow_pgt_lookup(struct gmap *sg, unsigned long saddr,
+ unsigned long *pgt, int *dat_protection)
+{
+ unsigned long *table;
+ struct page *page;
+ int rc;
+
+ BUG_ON(!gmap_is_shadow(sg));
+ spin_lock(&sg->guest_table_lock);
+ table = gmap_table_walk(sg, saddr, 1); /* get segment pointer */
+ if (table && !(*table & _SEGMENT_ENTRY_INVALID)) {
+ /* Shadow page tables are full pages (pte+pgste) */
+ page = pfn_to_page(*table >> PAGE_SHIFT);
+ *pgt = page->index;
+ *dat_protection = !!(*table & _SEGMENT_ENTRY_PROTECT);
+ rc = 0;
+ } else {
+ rc = -EAGAIN;
+ }
+ spin_unlock(&sg->guest_table_lock);
+ return rc;
+
+}
+EXPORT_SYMBOL_GPL(gmap_shadow_pgt_lookup);
+
+/**
+ * gmap_shadow_pgt - instantiate a shadow page table
+ * @sg: pointer to the shadow guest address space structure
+ * @saddr: faulting address in the shadow gmap
+ * @pgt: parent gmap address of the page table to get shadowed
+ *
+ * Returns 0 if successfully shadowed or already shadowed, -EAGAIN if the
+ * shadow table structure is incomplete, -ENOMEM if out of memory,
+ * -EFAULT if an address in the parent gmap could not be resolved and
+ *
+ * Called with gmap->mm->mmap_sem in read
+ */
+int gmap_shadow_pgt(struct gmap *sg, unsigned long saddr, unsigned long pgt)
+{
+ unsigned long raddr, origin;
+ unsigned long *s_pgt, *table;
+ struct page *page;
+ int rc;
+
+ BUG_ON(!gmap_is_shadow(sg));
+ /* Allocate a shadow page table */
+ page = page_table_alloc_pgste(sg->mm);
+ if (!page)
+ return -ENOMEM;
+ page->index = pgt & _SEGMENT_ENTRY_ORIGIN;
+ s_pgt = (unsigned long *) page_to_phys(page);
+ /* Install shadow page table */
+ spin_lock(&sg->guest_table_lock);
+ table = gmap_table_walk(sg, saddr, 1); /* get segment pointer */
+ if (!table) {
+ rc = -EAGAIN; /* Race with unshadow */
+ goto out_free;
+ }
+ if (!(*table & _SEGMENT_ENTRY_INVALID)) {
+ rc = 0; /* Already established */
+ goto out_free;
+ }
+ *table = (unsigned long) s_pgt | _SEGMENT_ENTRY |
+ (pgt & _SEGMENT_ENTRY_PROTECT);
+ list_add(&page->lru, &sg->pt_list);
+ spin_unlock(&sg->guest_table_lock);
+ /* Make pgt read-only in parent gmap page table (not the pgste) */
+ raddr = (saddr & 0xfffffffffff00000UL) | _SHADOW_RMAP_SEGMENT;
+ origin = pgt & _SEGMENT_ENTRY_ORIGIN & PAGE_MASK;
+ rc = gmap_protect_rmap(sg, raddr, origin, PAGE_SIZE, PROT_READ);
+ if (rc) {
+ spin_lock(&sg->guest_table_lock);
+ gmap_unshadow_pgt(sg, raddr);
+ spin_unlock(&sg->guest_table_lock);
+ }
+ return rc;
+out_free:
+ spin_unlock(&sg->guest_table_lock);
+ page_table_free_pgste(page);
+ return rc;
+
+}
+EXPORT_SYMBOL_GPL(gmap_shadow_pgt);
+
+/**
+ * gmap_shadow_page - create a shadow page mapping
+ * @sg: pointer to the shadow guest address space structure
+ * @saddr: faulting address in the shadow gmap
+ * @paddr: parent gmap address to get mapped at @saddr
+ * @write: =1 map r/w, =0 map r/o
+ *
+ * Returns 0 if successfully shadowed or already shadowed, -EAGAIN if the
+ * shadow table structure is incomplete, -ENOMEM if out of memory and
+ * -EFAULT if an address in the parent gmap could not be resolved.
+ *
+ * Called with sg->mm->mmap_sem in read.
+ */
+int gmap_shadow_page(struct gmap *sg, unsigned long saddr,
+ unsigned long paddr, int write)
+{
+ struct gmap *parent;
+ struct gmap_rmap *rmap;
+ unsigned long vmaddr;
+ spinlock_t *ptl;
+ pte_t *sptep, *tptep;
+ int rc;
+
+ BUG_ON(!gmap_is_shadow(sg));
+ parent = sg->parent;
+
+ rmap = kzalloc(sizeof(*rmap), GFP_KERNEL);
+ if (!rmap)
+ return -ENOMEM;
+ rmap->raddr = (saddr & PAGE_MASK) | _SHADOW_RMAP_PGTABLE;
+
+ while (1) {
+ vmaddr = __gmap_translate(parent, paddr);
+ if (IS_ERR_VALUE(vmaddr)) {
+ rc = vmaddr;
+ break;
+ }
+ rc = radix_tree_preload(GFP_KERNEL);
+ if (rc)
+ break;
+ rc = -EAGAIN;
+ sptep = gmap_pte_op_walk(parent, paddr, &ptl);
+ if (sptep) {
+ spin_lock(&sg->guest_table_lock);
+ /* Get page table pointer */
+ tptep = (pte_t *) gmap_table_walk(sg, saddr, 0);
+ if (!tptep) {
+ spin_unlock(&sg->guest_table_lock);
+ gmap_pte_op_end(ptl);
+ radix_tree_preload_end();
+ break;
+ }
+ rc = ptep_shadow_pte(sg->mm, saddr,
+ sptep, tptep, write);
+ if (rc > 0) {
+ /* Success and a new mapping */
+ gmap_insert_rmap(sg, vmaddr, rmap);
+ rmap = NULL;
+ rc = 0;
+ }
+ gmap_pte_op_end(ptl);
+ spin_unlock(&sg->guest_table_lock);
+ }
+ radix_tree_preload_end();
+ if (!rc)
+ break;
+ rc = gmap_pte_op_fixup(parent, paddr, vmaddr);
+ if (rc)
+ break;
+ }
+ kfree(rmap);
+ return rc;
+}
+EXPORT_SYMBOL_GPL(gmap_shadow_page);
+
+/**
+ * gmap_shadow_notify - handle notifications for shadow gmap
+ *
+ * Called with sg->parent->shadow_lock.
+ */
+static void gmap_shadow_notify(struct gmap *sg, unsigned long vmaddr,
+ unsigned long offset, pte_t *pte)
+{
+ struct gmap_rmap *rmap, *rnext, *head;
+ unsigned long gaddr, start, end, bits, raddr;
+ unsigned long *table;
+
+ BUG_ON(!gmap_is_shadow(sg));
+ spin_lock(&sg->parent->guest_table_lock);
+ table = radix_tree_lookup(&sg->parent->host_to_guest,
+ vmaddr >> PMD_SHIFT);
+ gaddr = table ? __gmap_segment_gaddr(table) + offset : 0;
+ spin_unlock(&sg->parent->guest_table_lock);
+ if (!table)
+ return;
+
+ spin_lock(&sg->guest_table_lock);
+ if (sg->removed) {
+ spin_unlock(&sg->guest_table_lock);
+ return;
+ }
+ /* Check for top level table */
+ start = sg->orig_asce & _ASCE_ORIGIN;
+ end = start + ((sg->orig_asce & _ASCE_TABLE_LENGTH) + 1) * 4096;
+ if (gaddr >= start && gaddr < end) {
+ /* The complete shadow table has to go */
+ gmap_unshadow(sg);
+ spin_unlock(&sg->guest_table_lock);
+ list_del(&sg->list);
+ gmap_put(sg);
+ return;
+ }
+ /* Remove the page table tree from on specific entry */
+ head = radix_tree_delete(&sg->host_to_rmap, vmaddr >> 12);
+ gmap_for_each_rmap_safe(rmap, rnext, head) {
+ bits = rmap->raddr & _SHADOW_RMAP_MASK;
+ raddr = rmap->raddr ^ bits;
+ switch (bits) {
+ case _SHADOW_RMAP_REGION1:
+ gmap_unshadow_r2t(sg, raddr);
+ break;
+ case _SHADOW_RMAP_REGION2:
+ gmap_unshadow_r3t(sg, raddr);
+ break;
+ case _SHADOW_RMAP_REGION3:
+ gmap_unshadow_sgt(sg, raddr);
+ break;
+ case _SHADOW_RMAP_SEGMENT:
+ gmap_unshadow_pgt(sg, raddr);
+ break;
+ case _SHADOW_RMAP_PGTABLE:
+ gmap_unshadow_page(sg, raddr);
+ break;
+ }
+ kfree(rmap);
+ }
+ spin_unlock(&sg->guest_table_lock);
+}
+
+/**
* ptep_notify - call all invalidation callbacks for a specific pte.
* @mm: pointer to the process mm_struct
* @addr: virtual address in the process address space
* @pte: pointer to the page table entry
+ * @bits: bits from the pgste that caused the notify call
*
* This function is assumed to be called with the page table lock held
* for the pte to notify.
*/
-void ptep_notify(struct mm_struct *mm, unsigned long vmaddr, pte_t *pte)
+void ptep_notify(struct mm_struct *mm, unsigned long vmaddr,
+ pte_t *pte, unsigned long bits)
{
unsigned long offset, gaddr;
unsigned long *table;
- struct gmap *gmap;
+ struct gmap *gmap, *sg, *next;
offset = ((unsigned long) pte) & (255 * sizeof(pte_t));
offset = offset * (4096 / sizeof(pte_t));
rcu_read_lock();
list_for_each_entry_rcu(gmap, &mm->context.gmap_list, list) {
+ if (!list_empty(&gmap->children) && (bits & PGSTE_VSIE_BIT)) {
+ spin_lock(&gmap->shadow_lock);
+ list_for_each_entry_safe(sg, next,
+ &gmap->children, list)
+ gmap_shadow_notify(sg, vmaddr, offset, pte);
+ spin_unlock(&gmap->shadow_lock);
+ }
+ if (!(bits & PGSTE_IN_BIT))
+ continue;
spin_lock(&gmap->guest_table_lock);
table = radix_tree_lookup(&gmap->host_to_guest,
vmaddr >> PMD_SHIFT);
diff --git a/arch/s390/mm/pgalloc.c b/arch/s390/mm/pgalloc.c
index 7be1f94..9c57a29 100644
--- a/arch/s390/mm/pgalloc.c
+++ b/arch/s390/mm/pgalloc.c
@@ -137,6 +137,29 @@ static inline unsigned int atomic_xor_bits(atomic_t *v, unsigned int bits)
return new;
}
+#ifdef CONFIG_PGSTE
+
+struct page *page_table_alloc_pgste(struct mm_struct *mm)
+{
+ struct page *page;
+ unsigned long *table;
+
+ page = alloc_page(GFP_KERNEL|__GFP_REPEAT);
+ if (page) {
+ table = (unsigned long *) page_to_phys(page);
+ clear_table(table, _PAGE_INVALID, PAGE_SIZE/2);
+ clear_table(table + PTRS_PER_PTE, 0, PAGE_SIZE/2);
+ }
+ return page;
+}
+
+void page_table_free_pgste(struct page *page)
+{
+ __free_page(page);
+}
+
+#endif /* CONFIG_PGSTE */
+
/*
* page table entry allocation/free routines.
*/
diff --git a/arch/s390/mm/pgtable.c b/arch/s390/mm/pgtable.c
index ab65fb1..5b02583 100644
--- a/arch/s390/mm/pgtable.c
+++ b/arch/s390/mm/pgtable.c
@@ -184,9 +184,12 @@ static inline pgste_t pgste_pte_notify(struct mm_struct *mm,
pte_t *ptep, pgste_t pgste)
{
#ifdef CONFIG_PGSTE
- if (pgste_val(pgste) & PGSTE_IN_BIT) {
- pgste_val(pgste) &= ~PGSTE_IN_BIT;
- ptep_notify(mm, addr, ptep);
+ unsigned long bits;
+
+ bits = pgste_val(pgste) & (PGSTE_IN_BIT | PGSTE_VSIE_BIT);
+ if (bits) {
+ pgste_val(pgste) ^= bits;
+ ptep_notify(mm, addr, ptep, bits);
}
#endif
return pgste;
@@ -420,12 +423,13 @@ void ptep_set_notify(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
* @addr: virtual address in the guest address space
* @ptep: pointer to the page table entry
* @prot: indicates guest access rights: PROT_NONE, PROT_READ or PROT_WRITE
+ * @bit: pgste bit to set (e.g. for notification)
*
* Returns 0 if the access rights were changed and -EAGAIN if the current
* and requested access rights are incompatible.
*/
int ptep_force_prot(struct mm_struct *mm, unsigned long addr,
- pte_t *ptep, int prot)
+ pte_t *ptep, int prot, unsigned long bit)
{
pte_t entry;
pgste_t pgste;
@@ -441,7 +445,7 @@ int ptep_force_prot(struct mm_struct *mm, unsigned long addr,
pgste_set_unlock(ptep, pgste);
return -EAGAIN;
}
- /* Change access rights and set the pgste notification bit */
+ /* Change access rights and set pgste bit */
if (prot == PROT_NONE && !pte_i) {
ptep_flush_direct(mm, addr, ptep);
pgste = pgste_update_all(entry, pgste, mm);
@@ -452,12 +456,53 @@ int ptep_force_prot(struct mm_struct *mm, unsigned long addr,
pte_val(entry) &= ~_PAGE_INVALID;
pte_val(entry) |= _PAGE_PROTECT;
}
- pgste_val(pgste) |= PGSTE_IN_BIT;
+ pgste_val(pgste) |= bit;
pgste = pgste_set_pte(ptep, pgste, entry);
pgste_set_unlock(ptep, pgste);
return 0;
}
+int ptep_shadow_pte(struct mm_struct *mm, unsigned long saddr,
+ pte_t *sptep, pte_t *tptep, int write)
+{
+ pgste_t spgste, tpgste;
+ pte_t spte, tpte;
+ int rc = -EAGAIN;
+
+ spgste = pgste_get_lock(sptep);
+ spte = *sptep;
+ if (!(pte_val(spte) & _PAGE_INVALID) &&
+ !(pte_val(spte) & _PAGE_PROTECT)) {
+ rc = 0;
+ if (!(pte_val(*tptep) & _PAGE_INVALID))
+ /* Update existing mapping */
+ ptep_flush_direct(mm, saddr, tptep);
+ else
+ rc = 1;
+ pgste_val(spgste) |= PGSTE_VSIE_BIT;
+ tpgste = pgste_get_lock(tptep);
+ pte_val(tpte) = (pte_val(spte) & PAGE_MASK) |
+ (write ? 0 : _PAGE_PROTECT);
+ /* don't touch the storage key - it belongs to parent pgste */
+ tpgste = pgste_set_pte(tptep, tpgste, tpte);
+ pgste_set_unlock(tptep, tpgste);
+ }
+ pgste_set_unlock(sptep, spgste);
+ return rc;
+}
+
+void ptep_unshadow_pte(struct mm_struct *mm, unsigned long saddr, pte_t *ptep)
+{
+ pgste_t pgste;
+
+ pgste = pgste_get_lock(ptep);
+ /* notifier is called by the caller */
+ ptep_flush_direct(mm, saddr, ptep);
+ /* don't touch the storage key - it belongs to parent pgste */
+ pgste = pgste_set_pte(ptep, pgste, __pte(_PAGE_INVALID));
+ pgste_set_unlock(ptep, pgste);
+}
+
static void ptep_zap_swap_entry(struct mm_struct *mm, swp_entry_t entry)
{
if (!non_swap_entry(entry))
--
2.5.5
^ permalink raw reply related [flat|nested] 53+ messages in thread* [GIT PULL 06/51] s390/mm: add kvm shadow fault function
2016-06-21 13:12 [GIT PULL 00/51] KVM: s390: vSIE (nested virtualization) feature for 4.8 (kvm/next) Christian Borntraeger
` (4 preceding siblings ...)
2016-06-21 13:12 ` [GIT PULL 05/51] s390/mm: add shadow gmap support Christian Borntraeger
@ 2016-06-21 13:12 ` Christian Borntraeger
2016-06-21 13:12 ` [GIT PULL 07/51] s390/mm: flush tlb of shadows in all situations Christian Borntraeger
` (45 subsequent siblings)
51 siblings, 0 replies; 53+ messages in thread
From: Christian Borntraeger @ 2016-06-21 13:12 UTC (permalink / raw)
To: Paolo Bonzini, Radim Krčmář
Cc: KVM, Cornelia Huck, linux-s390, Christian Borntraeger,
David Hildenbrand, Martin Schwidefsky
From: Martin Schwidefsky <schwidefsky@de.ibm.com>
This patch introduces function kvm_s390_shadow_fault() used to resolve a
fault on a shadow gmap. This function will do validity checking and
build up the shadow page table hierarchy in order to fault in the
requested page into the shadow page table structure.
If an exception occurs while shadowing, guest 2 has to be notified about
it using either an exception or a program interrupt intercept. If
concurrent unshadowing occurres, this function will simply return with
-EAGAIN and the caller has to retry.
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
arch/s390/kvm/gaccess.c | 168 ++++++++++++++++++++++++++++++++++++++++++++++++
arch/s390/kvm/gaccess.h | 2 +
2 files changed, 170 insertions(+)
diff --git a/arch/s390/kvm/gaccess.c b/arch/s390/kvm/gaccess.c
index 8e245e7..ba49852 100644
--- a/arch/s390/kvm/gaccess.c
+++ b/arch/s390/kvm/gaccess.c
@@ -8,6 +8,7 @@
#include <linux/vmalloc.h>
#include <linux/err.h>
#include <asm/pgtable.h>
+#include <asm/gmap.h>
#include "kvm-s390.h"
#include "gaccess.h"
#include <asm/switch_to.h>
@@ -946,3 +947,170 @@ int kvm_s390_check_low_addr_prot_real(struct kvm_vcpu *vcpu, unsigned long gra)
return 0;
return trans_exc(vcpu, PGM_PROTECTION, gra, 0, GACC_STORE, PROT_TYPE_LA);
}
+
+/**
+ * kvm_s390_shadow_tables - walk the guest page table and create shadow tables
+ * @sg: pointer to the shadow guest address space structure
+ * @saddr: faulting address in the shadow gmap
+ * @pgt: pointer to the page table address result
+ */
+static int kvm_s390_shadow_tables(struct gmap *sg, unsigned long saddr,
+ unsigned long *pgt, int *dat_protection)
+{
+ struct gmap *parent;
+ union asce asce;
+ union vaddress vaddr;
+ unsigned long ptr;
+ int rc;
+
+ parent = sg->parent;
+ vaddr.addr = saddr;
+ asce.val = sg->orig_asce;
+ ptr = asce.origin * 4096;
+ switch (asce.dt) {
+ case ASCE_TYPE_REGION1:
+ if (vaddr.rfx01 > asce.tl)
+ return PGM_REGION_FIRST_TRANS;
+ break;
+ case ASCE_TYPE_REGION2:
+ if (vaddr.rfx)
+ return PGM_ASCE_TYPE;
+ if (vaddr.rsx01 > asce.tl)
+ return PGM_REGION_SECOND_TRANS;
+ break;
+ case ASCE_TYPE_REGION3:
+ if (vaddr.rfx || vaddr.rsx)
+ return PGM_ASCE_TYPE;
+ if (vaddr.rtx01 > asce.tl)
+ return PGM_REGION_THIRD_TRANS;
+ break;
+ case ASCE_TYPE_SEGMENT:
+ if (vaddr.rfx || vaddr.rsx || vaddr.rtx)
+ return PGM_ASCE_TYPE;
+ if (vaddr.sx01 > asce.tl)
+ return PGM_SEGMENT_TRANSLATION;
+ break;
+ }
+
+ switch (asce.dt) {
+ case ASCE_TYPE_REGION1: {
+ union region1_table_entry rfte;
+
+ rc = gmap_read_table(parent, ptr + vaddr.rfx * 8, &rfte.val);
+ if (rc)
+ return rc;
+ if (rfte.i)
+ return PGM_REGION_FIRST_TRANS;
+ if (rfte.tt != TABLE_TYPE_REGION1)
+ return PGM_TRANSLATION_SPEC;
+ if (vaddr.rsx01 < rfte.tf || vaddr.rsx01 > rfte.tl)
+ return PGM_REGION_SECOND_TRANS;
+ rc = gmap_shadow_r2t(sg, saddr, rfte.val);
+ if (rc)
+ return rc;
+ ptr = rfte.rto * 4096;
+ /* fallthrough */
+ }
+ case ASCE_TYPE_REGION2: {
+ union region2_table_entry rste;
+
+ rc = gmap_read_table(parent, ptr + vaddr.rsx * 8, &rste.val);
+ if (rc)
+ return rc;
+ if (rste.i)
+ return PGM_REGION_SECOND_TRANS;
+ if (rste.tt != TABLE_TYPE_REGION2)
+ return PGM_TRANSLATION_SPEC;
+ if (vaddr.rtx01 < rste.tf || vaddr.rtx01 > rste.tl)
+ return PGM_REGION_THIRD_TRANS;
+ rc = gmap_shadow_r3t(sg, saddr, rste.val);
+ if (rc)
+ return rc;
+ ptr = rste.rto * 4096;
+ /* fallthrough */
+ }
+ case ASCE_TYPE_REGION3: {
+ union region3_table_entry rtte;
+
+ rc = gmap_read_table(parent, ptr + vaddr.rtx * 8, &rtte.val);
+ if (rc)
+ return rc;
+ if (rtte.i)
+ return PGM_REGION_THIRD_TRANS;
+ if (rtte.tt != TABLE_TYPE_REGION3)
+ return PGM_TRANSLATION_SPEC;
+ if (vaddr.sx01 < rtte.fc0.tf || vaddr.sx01 > rtte.fc0.tl)
+ return PGM_SEGMENT_TRANSLATION;
+ rc = gmap_shadow_sgt(sg, saddr, rtte.val);
+ if (rc)
+ return rc;
+ ptr = rtte.fc0.sto * 4096;
+ /* fallthrough */
+ }
+ case ASCE_TYPE_SEGMENT: {
+ union segment_table_entry ste;
+
+ rc = gmap_read_table(parent, ptr + vaddr.sx * 8, &ste.val);
+ if (rc)
+ return rc;
+ if (ste.i)
+ return PGM_SEGMENT_TRANSLATION;
+ if (ste.tt != TABLE_TYPE_SEGMENT)
+ return PGM_TRANSLATION_SPEC;
+ if (ste.cs && asce.p)
+ return PGM_TRANSLATION_SPEC;
+ *dat_protection = ste.fc0.p;
+ rc = gmap_shadow_pgt(sg, saddr, ste.val);
+ if (rc)
+ return rc;
+ ptr = ste.fc0.pto * 2048;
+ }
+ }
+ /* Return the parent address of the page table */
+ *pgt = ptr;
+ return 0;
+}
+
+/**
+ * kvm_s390_shadow_fault - handle fault on a shadow page table
+ * @sg: pointer to the shadow guest address space structure
+ * @saddr: faulting address in the shadow gmap
+ * @write: =1 map r/w, =0 map r/o
+ *
+ * Returns: - 0 if the shadow fault was successfully resolved
+ * - > 0 (pgm exception code) on exceptions while faulting
+ * - -EAGAIN if the caller can retry immediately
+ * - -EFAULT when accessing invalid guest addresses
+ * - -ENOMEM if out of memory
+ */
+int kvm_s390_shadow_fault(struct gmap *sg, unsigned long saddr, int write)
+{
+ union vaddress vaddr;
+ union page_table_entry pte;
+ unsigned long pgt;
+ int dat_protection;
+ int rc;
+
+ rc = gmap_shadow_pgt_lookup(sg, saddr, &pgt, &dat_protection);
+ if (rc) {
+ rc = kvm_s390_shadow_tables(sg, saddr, &pgt, &dat_protection);
+ if (rc)
+ return rc;
+ }
+
+ vaddr.addr = saddr;
+ rc = gmap_read_table(sg->parent, pgt + vaddr.px * 8, &pte.val);
+ if (rc)
+ return rc;
+ if (pte.i)
+ return PGM_PAGE_TRANSLATION;
+ if (pte.z || pte.co)
+ return PGM_TRANSLATION_SPEC;
+ dat_protection |= pte.p;
+ if (write && dat_protection)
+ return PGM_PROTECTION;
+ rc = gmap_shadow_page(sg, saddr, pte.pfra * 4096, write);
+ if (rc)
+ return rc;
+ return 0;
+}
diff --git a/arch/s390/kvm/gaccess.h b/arch/s390/kvm/gaccess.h
index df0a79d..e5ec473 100644
--- a/arch/s390/kvm/gaccess.h
+++ b/arch/s390/kvm/gaccess.h
@@ -361,4 +361,6 @@ void ipte_unlock(struct kvm_vcpu *vcpu);
int ipte_lock_held(struct kvm_vcpu *vcpu);
int kvm_s390_check_low_addr_prot_real(struct kvm_vcpu *vcpu, unsigned long gra);
+int kvm_s390_shadow_fault(struct gmap *shadow, unsigned long saddr, int write);
+
#endif /* __KVM_S390_GACCESS_H */
--
2.5.5
^ permalink raw reply related [flat|nested] 53+ messages in thread* [GIT PULL 07/51] s390/mm: flush tlb of shadows in all situations
2016-06-21 13:12 [GIT PULL 00/51] KVM: s390: vSIE (nested virtualization) feature for 4.8 (kvm/next) Christian Borntraeger
` (5 preceding siblings ...)
2016-06-21 13:12 ` [GIT PULL 06/51] s390/mm: add kvm shadow fault function Christian Borntraeger
@ 2016-06-21 13:12 ` Christian Borntraeger
2016-06-21 13:12 ` [GIT PULL 08/51] s390/mm: shadow pages with real guest requested protection Christian Borntraeger
` (44 subsequent siblings)
51 siblings, 0 replies; 53+ messages in thread
From: Christian Borntraeger @ 2016-06-21 13:12 UTC (permalink / raw)
To: Paolo Bonzini, Radim Krčmář
Cc: KVM, Cornelia Huck, linux-s390, Christian Borntraeger,
David Hildenbrand, Martin Schwidefsky
From: David Hildenbrand <dahi@linux.vnet.ibm.com>
For now, the tlb of shadow gmap is only flushed when the parent is removed,
not when it is removed upfront. Therefore other shadow gmaps can reuse the
tables without the tlb getting flushed.
Fix this by simply flushing the tlb
1. Before the shadow tables are removed (analogouos to other unshadow functions)
2. When the gmap is freed and therefore the top level pages are freed.
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
arch/s390/mm/gmap.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)
diff --git a/arch/s390/mm/gmap.c b/arch/s390/mm/gmap.c
index 6695a09..b02d0d0 100644
--- a/arch/s390/mm/gmap.c
+++ b/arch/s390/mm/gmap.c
@@ -173,6 +173,9 @@ static void gmap_free(struct gmap *gmap)
{
struct page *page, *next;
+ /* Flush tlb of all gmaps (if not already done for shadows) */
+ if (!(gmap_is_shadow(gmap) && gmap->removed))
+ gmap_flush_tlb(gmap);
/* Free all segment & region tables. */
list_for_each_entry_safe(page, next, &gmap->crst_list, lru)
__free_pages(page, 2);
@@ -226,13 +229,10 @@ void gmap_remove(struct gmap *gmap)
{
struct gmap *sg, *next;
- /* Flush tlb. */
- gmap_flush_tlb(gmap);
/* Remove all shadow gmaps linked to this gmap */
if (!list_empty(&gmap->children)) {
spin_lock(&gmap->shadow_lock);
list_for_each_entry_safe(sg, next, &gmap->children, list) {
- gmap_flush_tlb(sg);
list_del(&sg->list);
gmap_put(sg);
}
@@ -1360,6 +1360,7 @@ static void gmap_unshadow(struct gmap *sg)
return;
sg->removed = 1;
gmap_call_notifier(sg, 0, -1UL);
+ gmap_flush_tlb(sg);
table = (unsigned long *)(sg->asce & _ASCE_ORIGIN);
switch (sg->asce & _ASCE_TYPE_MASK) {
case _ASCE_TYPE_REGION1:
--
2.5.5
^ permalink raw reply related [flat|nested] 53+ messages in thread* [GIT PULL 08/51] s390/mm: shadow pages with real guest requested protection
2016-06-21 13:12 [GIT PULL 00/51] KVM: s390: vSIE (nested virtualization) feature for 4.8 (kvm/next) Christian Borntraeger
` (6 preceding siblings ...)
2016-06-21 13:12 ` [GIT PULL 07/51] s390/mm: flush tlb of shadows in all situations Christian Borntraeger
@ 2016-06-21 13:12 ` Christian Borntraeger
2016-06-21 13:12 ` [GIT PULL 09/51] s390/mm: avoid races on region/segment/page table shadowing Christian Borntraeger
` (43 subsequent siblings)
51 siblings, 0 replies; 53+ messages in thread
From: Christian Borntraeger @ 2016-06-21 13:12 UTC (permalink / raw)
To: Paolo Bonzini, Radim Krčmář
Cc: KVM, Cornelia Huck, linux-s390, Christian Borntraeger,
David Hildenbrand, Martin Schwidefsky
From: David Hildenbrand <dahi@linux.vnet.ibm.com>
We really want to avoid manually handling protection for nested
virtualization. By shadowing pages with the protection the guest asked us
for, the SIE can handle most protection-related actions for us (e.g.
special handling for MVPG) and we can directly forward protection
exceptions to the guest.
PTEs will now always be shadowed with the correct _PAGE_PROTECT flag.
Unshadowing will take care of any guest changes to the parent PTE and
any host changes to the host PTE. If the host PTE doesn't have the
fitting access rights or is not available, we have to fix it up.
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
arch/s390/include/asm/gmap.h | 3 +--
arch/s390/include/asm/pgtable.h | 2 +-
arch/s390/kvm/gaccess.c | 2 +-
arch/s390/mm/gmap.c | 12 +++++-------
arch/s390/mm/pgtable.c | 16 +++++++---------
5 files changed, 15 insertions(+), 20 deletions(-)
diff --git a/arch/s390/include/asm/gmap.h b/arch/s390/include/asm/gmap.h
index 58e65ee..4a47055 100644
--- a/arch/s390/include/asm/gmap.h
+++ b/arch/s390/include/asm/gmap.h
@@ -110,8 +110,7 @@ int gmap_shadow_sgt(struct gmap *sg, unsigned long saddr, unsigned long sgt);
int gmap_shadow_pgt(struct gmap *sg, unsigned long saddr, unsigned long pgt);
int gmap_shadow_pgt_lookup(struct gmap *sg, unsigned long saddr,
unsigned long *pgt, int *dat_protection);
-int gmap_shadow_page(struct gmap *sg, unsigned long saddr,
- unsigned long paddr, int write);
+int gmap_shadow_page(struct gmap *sg, unsigned long saddr, pte_t pte);
void gmap_register_pte_notifier(struct gmap_notifier *);
void gmap_unregister_pte_notifier(struct gmap_notifier *);
diff --git a/arch/s390/include/asm/pgtable.h b/arch/s390/include/asm/pgtable.h
index a6e7fc8..c7ebba4 100644
--- a/arch/s390/include/asm/pgtable.h
+++ b/arch/s390/include/asm/pgtable.h
@@ -895,7 +895,7 @@ void ptep_zap_unused(struct mm_struct *mm, unsigned long addr,
pte_t *ptep , int reset);
void ptep_zap_key(struct mm_struct *mm, unsigned long addr, pte_t *ptep);
int ptep_shadow_pte(struct mm_struct *mm, unsigned long saddr,
- pte_t *sptep, pte_t *tptep, int write);
+ pte_t *sptep, pte_t *tptep, pte_t pte);
void ptep_unshadow_pte(struct mm_struct *mm, unsigned long saddr, pte_t *ptep);
bool test_and_clear_guest_dirty(struct mm_struct *mm, unsigned long address);
diff --git a/arch/s390/kvm/gaccess.c b/arch/s390/kvm/gaccess.c
index ba49852..c5f79c1 100644
--- a/arch/s390/kvm/gaccess.c
+++ b/arch/s390/kvm/gaccess.c
@@ -1109,7 +1109,7 @@ int kvm_s390_shadow_fault(struct gmap *sg, unsigned long saddr, int write)
dat_protection |= pte.p;
if (write && dat_protection)
return PGM_PROTECTION;
- rc = gmap_shadow_page(sg, saddr, pte.pfra * 4096, write);
+ rc = gmap_shadow_page(sg, saddr, __pte(pte.val));
if (rc)
return rc;
return 0;
diff --git a/arch/s390/mm/gmap.c b/arch/s390/mm/gmap.c
index b02d0d0..a57a87b 100644
--- a/arch/s390/mm/gmap.c
+++ b/arch/s390/mm/gmap.c
@@ -1743,8 +1743,7 @@ EXPORT_SYMBOL_GPL(gmap_shadow_pgt);
* gmap_shadow_page - create a shadow page mapping
* @sg: pointer to the shadow guest address space structure
* @saddr: faulting address in the shadow gmap
- * @paddr: parent gmap address to get mapped at @saddr
- * @write: =1 map r/w, =0 map r/o
+ * @pte: pte in parent gmap address space to get shadowed
*
* Returns 0 if successfully shadowed or already shadowed, -EAGAIN if the
* shadow table structure is incomplete, -ENOMEM if out of memory and
@@ -1752,12 +1751,11 @@ EXPORT_SYMBOL_GPL(gmap_shadow_pgt);
*
* Called with sg->mm->mmap_sem in read.
*/
-int gmap_shadow_page(struct gmap *sg, unsigned long saddr,
- unsigned long paddr, int write)
+int gmap_shadow_page(struct gmap *sg, unsigned long saddr, pte_t pte)
{
struct gmap *parent;
struct gmap_rmap *rmap;
- unsigned long vmaddr;
+ unsigned long vmaddr, paddr;
spinlock_t *ptl;
pte_t *sptep, *tptep;
int rc;
@@ -1771,6 +1769,7 @@ int gmap_shadow_page(struct gmap *sg, unsigned long saddr,
rmap->raddr = (saddr & PAGE_MASK) | _SHADOW_RMAP_PGTABLE;
while (1) {
+ paddr = pte_val(pte) & PAGE_MASK;
vmaddr = __gmap_translate(parent, paddr);
if (IS_ERR_VALUE(vmaddr)) {
rc = vmaddr;
@@ -1791,8 +1790,7 @@ int gmap_shadow_page(struct gmap *sg, unsigned long saddr,
radix_tree_preload_end();
break;
}
- rc = ptep_shadow_pte(sg->mm, saddr,
- sptep, tptep, write);
+ rc = ptep_shadow_pte(sg->mm, saddr, sptep, tptep, pte);
if (rc > 0) {
/* Success and a new mapping */
gmap_insert_rmap(sg, vmaddr, rmap);
diff --git a/arch/s390/mm/pgtable.c b/arch/s390/mm/pgtable.c
index 5b02583..293130b 100644
--- a/arch/s390/mm/pgtable.c
+++ b/arch/s390/mm/pgtable.c
@@ -463,29 +463,27 @@ int ptep_force_prot(struct mm_struct *mm, unsigned long addr,
}
int ptep_shadow_pte(struct mm_struct *mm, unsigned long saddr,
- pte_t *sptep, pte_t *tptep, int write)
+ pte_t *sptep, pte_t *tptep, pte_t pte)
{
pgste_t spgste, tpgste;
pte_t spte, tpte;
int rc = -EAGAIN;
+ if (!(pte_val(*tptep) & _PAGE_INVALID))
+ return 0; /* already shadowed */
spgste = pgste_get_lock(sptep);
spte = *sptep;
if (!(pte_val(spte) & _PAGE_INVALID) &&
- !(pte_val(spte) & _PAGE_PROTECT)) {
- rc = 0;
- if (!(pte_val(*tptep) & _PAGE_INVALID))
- /* Update existing mapping */
- ptep_flush_direct(mm, saddr, tptep);
- else
- rc = 1;
+ !((pte_val(spte) & _PAGE_PROTECT) &&
+ !(pte_val(pte) & _PAGE_PROTECT))) {
pgste_val(spgste) |= PGSTE_VSIE_BIT;
tpgste = pgste_get_lock(tptep);
pte_val(tpte) = (pte_val(spte) & PAGE_MASK) |
- (write ? 0 : _PAGE_PROTECT);
+ (pte_val(pte) & _PAGE_PROTECT);
/* don't touch the storage key - it belongs to parent pgste */
tpgste = pgste_set_pte(tptep, tpgste, tpte);
pgste_set_unlock(tptep, tpgste);
+ rc = 1;
}
pgste_set_unlock(sptep, spgste);
return rc;
--
2.5.5
^ permalink raw reply related [flat|nested] 53+ messages in thread* [GIT PULL 09/51] s390/mm: avoid races on region/segment/page table shadowing
2016-06-21 13:12 [GIT PULL 00/51] KVM: s390: vSIE (nested virtualization) feature for 4.8 (kvm/next) Christian Borntraeger
` (7 preceding siblings ...)
2016-06-21 13:12 ` [GIT PULL 08/51] s390/mm: shadow pages with real guest requested protection Christian Borntraeger
@ 2016-06-21 13:12 ` Christian Borntraeger
2016-06-21 13:12 ` [GIT PULL 10/51] s390/mm: fix races on gmap_shadow creation Christian Borntraeger
` (42 subsequent siblings)
51 siblings, 0 replies; 53+ messages in thread
From: Christian Borntraeger @ 2016-06-21 13:12 UTC (permalink / raw)
To: Paolo Bonzini, Radim Krčmář
Cc: KVM, Cornelia Huck, linux-s390, Christian Borntraeger,
David Hildenbrand, Martin Schwidefsky
From: David Hildenbrand <dahi@linux.vnet.ibm.com>
We have to unlock sg->guest_table_lock in order to call
gmap_protect_rmap(). If we sleep just before that call, another VCPU
might pick up that shadowed page table (while it is not protected yet)
and use it.
In order to avoid these races, we have to introduce a third state -
"origin set but still invalid" for an entry. This way, we can avoid
another thread already using the entry before the table is fully protected.
As soon as everything is set up, we can clear the invalid bit - if we
had no race with the unshadowing code.
Suggested-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
arch/s390/mm/gmap.c | 97 ++++++++++++++++++++++++++++++++++++++---------------
1 file changed, 70 insertions(+), 27 deletions(-)
diff --git a/arch/s390/mm/gmap.c b/arch/s390/mm/gmap.c
index a57a87b..a396e58 100644
--- a/arch/s390/mm/gmap.c
+++ b/arch/s390/mm/gmap.c
@@ -1125,7 +1125,7 @@ static void gmap_unshadow_pgt(struct gmap *sg, unsigned long raddr)
BUG_ON(!gmap_is_shadow(sg));
ste = gmap_table_walk(sg, raddr, 1); /* get segment pointer */
- if (!ste || *ste & _SEGMENT_ENTRY_INVALID)
+ if (!ste || !(*ste & _SEGMENT_ENTRY_ORIGIN))
return;
gmap_call_notifier(sg, raddr, raddr + (1UL << 20) - 1);
sto = (unsigned long) (ste - ((raddr >> 20) & 0x7ff));
@@ -1157,7 +1157,7 @@ static void __gmap_unshadow_sgt(struct gmap *sg, unsigned long raddr,
BUG_ON(!gmap_is_shadow(sg));
asce = (unsigned long) sgt | _ASCE_TYPE_SEGMENT;
for (i = 0; i < 2048; i++, raddr += 1UL << 20) {
- if (sgt[i] & _SEGMENT_ENTRY_INVALID)
+ if (!(sgt[i] & _SEGMENT_ENTRY_ORIGIN))
continue;
pgt = (unsigned long *)(sgt[i] & _REGION_ENTRY_ORIGIN);
sgt[i] = _SEGMENT_ENTRY_EMPTY;
@@ -1183,7 +1183,7 @@ static void gmap_unshadow_sgt(struct gmap *sg, unsigned long raddr)
BUG_ON(!gmap_is_shadow(sg));
r3e = gmap_table_walk(sg, raddr, 2); /* get region-3 pointer */
- if (!r3e || *r3e & _REGION_ENTRY_INVALID)
+ if (!r3e || !(*r3e & _REGION_ENTRY_ORIGIN))
return;
gmap_call_notifier(sg, raddr, raddr + (1UL << 31) - 1);
r3o = (unsigned long) (r3e - ((raddr >> 31) & 0x7ff));
@@ -1215,7 +1215,7 @@ static void __gmap_unshadow_r3t(struct gmap *sg, unsigned long raddr,
BUG_ON(!gmap_is_shadow(sg));
asce = (unsigned long) r3t | _ASCE_TYPE_REGION3;
for (i = 0; i < 2048; i++, raddr += 1UL << 31) {
- if (r3t[i] & _REGION_ENTRY_INVALID)
+ if (!(r3t[i] & _REGION_ENTRY_ORIGIN))
continue;
sgt = (unsigned long *)(r3t[i] & _REGION_ENTRY_ORIGIN);
r3t[i] = _REGION3_ENTRY_EMPTY;
@@ -1241,7 +1241,7 @@ static void gmap_unshadow_r3t(struct gmap *sg, unsigned long raddr)
BUG_ON(!gmap_is_shadow(sg));
r2e = gmap_table_walk(sg, raddr, 3); /* get region-2 pointer */
- if (!r2e || *r2e & _REGION_ENTRY_INVALID)
+ if (!r2e || !(*r2e & _REGION_ENTRY_ORIGIN))
return;
gmap_call_notifier(sg, raddr, raddr + (1UL << 42) - 1);
r2o = (unsigned long) (r2e - ((raddr >> 42) & 0x7ff));
@@ -1273,7 +1273,7 @@ static void __gmap_unshadow_r2t(struct gmap *sg, unsigned long raddr,
BUG_ON(!gmap_is_shadow(sg));
asce = (unsigned long) r2t | _ASCE_TYPE_REGION2;
for (i = 0; i < 2048; i++, raddr += 1UL << 42) {
- if (r2t[i] & _REGION_ENTRY_INVALID)
+ if (!(r2t[i] & _REGION_ENTRY_ORIGIN))
continue;
r3t = (unsigned long *)(r2t[i] & _REGION_ENTRY_ORIGIN);
r2t[i] = _REGION2_ENTRY_EMPTY;
@@ -1299,7 +1299,7 @@ static void gmap_unshadow_r2t(struct gmap *sg, unsigned long raddr)
BUG_ON(!gmap_is_shadow(sg));
r1e = gmap_table_walk(sg, raddr, 4); /* get region-1 pointer */
- if (!r1e || *r1e & _REGION_ENTRY_INVALID)
+ if (!r1e || !(*r1e & _REGION_ENTRY_ORIGIN))
return;
gmap_call_notifier(sg, raddr, raddr + (1UL << 53) - 1);
r1o = (unsigned long) (r1e - ((raddr >> 53) & 0x7ff));
@@ -1331,7 +1331,7 @@ static void __gmap_unshadow_r1t(struct gmap *sg, unsigned long raddr,
BUG_ON(!gmap_is_shadow(sg));
asce = (unsigned long) r1t | _ASCE_TYPE_REGION1;
for (i = 0; i < 2048; i++, raddr += 1UL << 53) {
- if (r1t[i] & _REGION_ENTRY_INVALID)
+ if (!(r1t[i] & _REGION_ENTRY_ORIGIN))
continue;
r2t = (unsigned long *)(r1t[i] & _REGION_ENTRY_ORIGIN);
__gmap_unshadow_r2t(sg, raddr, r2t);
@@ -1496,10 +1496,14 @@ int gmap_shadow_r2t(struct gmap *sg, unsigned long saddr, unsigned long r2t)
if (!(*table & _REGION_ENTRY_INVALID)) {
rc = 0; /* Already established */
goto out_free;
+ } else if (*table & _REGION_ENTRY_ORIGIN) {
+ rc = -EAGAIN; /* Race with shadow */
+ goto out_free;
}
crst_table_init(s_r2t, _REGION2_ENTRY_EMPTY);
- *table = (unsigned long) s_r2t |
- _REGION_ENTRY_LENGTH | _REGION_ENTRY_TYPE_R1;
+ /* mark as invalid as long as the parent table is not protected */
+ *table = (unsigned long) s_r2t | _REGION_ENTRY_LENGTH |
+ _REGION_ENTRY_TYPE_R1 | _REGION_ENTRY_INVALID;
list_add(&page->lru, &sg->crst_list);
spin_unlock(&sg->guest_table_lock);
/* Make r2t read-only in parent gmap page table */
@@ -1508,11 +1512,18 @@ int gmap_shadow_r2t(struct gmap *sg, unsigned long saddr, unsigned long r2t)
offset = ((r2t & _REGION_ENTRY_OFFSET) >> 6) * 4096;
len = ((r2t & _REGION_ENTRY_LENGTH) + 1) * 4096 - offset;
rc = gmap_protect_rmap(sg, raddr, origin + offset, len, PROT_READ);
- if (rc) {
- spin_lock(&sg->guest_table_lock);
+ spin_lock(&sg->guest_table_lock);
+ if (!rc) {
+ table = gmap_table_walk(sg, saddr, 4);
+ if (!table || (*table & _REGION_ENTRY_ORIGIN) !=
+ (unsigned long) s_r2t)
+ rc = -EAGAIN; /* Race with unshadow */
+ else
+ *table &= ~_REGION_ENTRY_INVALID;
+ } else {
gmap_unshadow_r2t(sg, raddr);
- spin_unlock(&sg->guest_table_lock);
}
+ spin_unlock(&sg->guest_table_lock);
return rc;
out_free:
spin_unlock(&sg->guest_table_lock);
@@ -1557,10 +1568,13 @@ int gmap_shadow_r3t(struct gmap *sg, unsigned long saddr, unsigned long r3t)
if (!(*table & _REGION_ENTRY_INVALID)) {
rc = 0; /* Already established */
goto out_free;
+ } else if (*table & _REGION_ENTRY_ORIGIN) {
+ rc = -EAGAIN; /* Race with shadow */
}
crst_table_init(s_r3t, _REGION3_ENTRY_EMPTY);
- *table = (unsigned long) s_r3t |
- _REGION_ENTRY_LENGTH | _REGION_ENTRY_TYPE_R2;
+ /* mark as invalid as long as the parent table is not protected */
+ *table = (unsigned long) s_r3t | _REGION_ENTRY_LENGTH |
+ _REGION_ENTRY_TYPE_R2 | _REGION_ENTRY_INVALID;
list_add(&page->lru, &sg->crst_list);
spin_unlock(&sg->guest_table_lock);
/* Make r3t read-only in parent gmap page table */
@@ -1569,11 +1583,18 @@ int gmap_shadow_r3t(struct gmap *sg, unsigned long saddr, unsigned long r3t)
offset = ((r3t & _REGION_ENTRY_OFFSET) >> 6) * 4096;
len = ((r3t & _REGION_ENTRY_LENGTH) + 1) * 4096 - offset;
rc = gmap_protect_rmap(sg, raddr, origin + offset, len, PROT_READ);
- if (rc) {
- spin_lock(&sg->guest_table_lock);
+ spin_lock(&sg->guest_table_lock);
+ if (!rc) {
+ table = gmap_table_walk(sg, saddr, 3);
+ if (!table || (*table & _REGION_ENTRY_ORIGIN) !=
+ (unsigned long) s_r3t)
+ rc = -EAGAIN; /* Race with unshadow */
+ else
+ *table &= ~_REGION_ENTRY_INVALID;
+ } else {
gmap_unshadow_r3t(sg, raddr);
- spin_unlock(&sg->guest_table_lock);
}
+ spin_unlock(&sg->guest_table_lock);
return rc;
out_free:
spin_unlock(&sg->guest_table_lock);
@@ -1618,10 +1639,14 @@ int gmap_shadow_sgt(struct gmap *sg, unsigned long saddr, unsigned long sgt)
if (!(*table & _REGION_ENTRY_INVALID)) {
rc = 0; /* Already established */
goto out_free;
+ } else if (*table & _REGION_ENTRY_ORIGIN) {
+ rc = -EAGAIN; /* Race with shadow */
+ goto out_free;
}
crst_table_init(s_sgt, _SEGMENT_ENTRY_EMPTY);
- *table = (unsigned long) s_sgt |
- _REGION_ENTRY_LENGTH | _REGION_ENTRY_TYPE_R3;
+ /* mark as invalid as long as the parent table is not protected */
+ *table = (unsigned long) s_sgt | _REGION_ENTRY_LENGTH |
+ _REGION_ENTRY_TYPE_R3 | _REGION_ENTRY_INVALID;
list_add(&page->lru, &sg->crst_list);
spin_unlock(&sg->guest_table_lock);
/* Make sgt read-only in parent gmap page table */
@@ -1630,11 +1655,18 @@ int gmap_shadow_sgt(struct gmap *sg, unsigned long saddr, unsigned long sgt)
offset = ((sgt & _REGION_ENTRY_OFFSET) >> 6) * 4096;
len = ((sgt & _REGION_ENTRY_LENGTH) + 1) * 4096 - offset;
rc = gmap_protect_rmap(sg, raddr, origin + offset, len, PROT_READ);
- if (rc) {
- spin_lock(&sg->guest_table_lock);
+ spin_lock(&sg->guest_table_lock);
+ if (!rc) {
+ table = gmap_table_walk(sg, saddr, 2);
+ if (!table || (*table & _REGION_ENTRY_ORIGIN) !=
+ (unsigned long) s_sgt)
+ rc = -EAGAIN; /* Race with unshadow */
+ else
+ *table &= ~_REGION_ENTRY_INVALID;
+ } else {
gmap_unshadow_sgt(sg, raddr);
- spin_unlock(&sg->guest_table_lock);
}
+ spin_unlock(&sg->guest_table_lock);
return rc;
out_free:
spin_unlock(&sg->guest_table_lock);
@@ -1716,20 +1748,31 @@ int gmap_shadow_pgt(struct gmap *sg, unsigned long saddr, unsigned long pgt)
if (!(*table & _SEGMENT_ENTRY_INVALID)) {
rc = 0; /* Already established */
goto out_free;
+ } else if (*table & _SEGMENT_ENTRY_ORIGIN) {
+ rc = -EAGAIN; /* Race with shadow */
+ goto out_free;
}
+ /* mark as invalid as long as the parent table is not protected */
*table = (unsigned long) s_pgt | _SEGMENT_ENTRY |
- (pgt & _SEGMENT_ENTRY_PROTECT);
+ (pgt & _SEGMENT_ENTRY_PROTECT) | _SEGMENT_ENTRY_INVALID;
list_add(&page->lru, &sg->pt_list);
spin_unlock(&sg->guest_table_lock);
/* Make pgt read-only in parent gmap page table (not the pgste) */
raddr = (saddr & 0xfffffffffff00000UL) | _SHADOW_RMAP_SEGMENT;
origin = pgt & _SEGMENT_ENTRY_ORIGIN & PAGE_MASK;
rc = gmap_protect_rmap(sg, raddr, origin, PAGE_SIZE, PROT_READ);
- if (rc) {
- spin_lock(&sg->guest_table_lock);
+ spin_lock(&sg->guest_table_lock);
+ if (!rc) {
+ table = gmap_table_walk(sg, saddr, 1);
+ if (!table || (*table & _SEGMENT_ENTRY_ORIGIN) !=
+ (unsigned long) s_pgt)
+ rc = -EAGAIN; /* Race with unshadow */
+ else
+ *table &= ~_SEGMENT_ENTRY_INVALID;
+ } else {
gmap_unshadow_pgt(sg, raddr);
- spin_unlock(&sg->guest_table_lock);
}
+ spin_unlock(&sg->guest_table_lock);
return rc;
out_free:
spin_unlock(&sg->guest_table_lock);
--
2.5.5
^ permalink raw reply related [flat|nested] 53+ messages in thread* [GIT PULL 10/51] s390/mm: fix races on gmap_shadow creation
2016-06-21 13:12 [GIT PULL 00/51] KVM: s390: vSIE (nested virtualization) feature for 4.8 (kvm/next) Christian Borntraeger
` (8 preceding siblings ...)
2016-06-21 13:12 ` [GIT PULL 09/51] s390/mm: avoid races on region/segment/page table shadowing Christian Borntraeger
@ 2016-06-21 13:12 ` Christian Borntraeger
2016-06-21 13:12 ` [GIT PULL 11/51] s390/mm: take the mmap_sem in kvm_s390_shadow_fault() Christian Borntraeger
` (41 subsequent siblings)
51 siblings, 0 replies; 53+ messages in thread
From: Christian Borntraeger @ 2016-06-21 13:12 UTC (permalink / raw)
To: Paolo Bonzini, Radim Krčmář
Cc: KVM, Cornelia Huck, linux-s390, Christian Borntraeger,
David Hildenbrand, Martin Schwidefsky
From: David Hildenbrand <dahi@linux.vnet.ibm.com>
Before any thread is allowed to use a gmap_shadow, it has to be fully
initialized. However, for invalidation to work properly, we have to
register the new gmap_shadow before we protect the parent gmap table.
Because locking is tricky, and we have to avoid duplicate gmaps, let's
introduce an initialized field, that signalizes other threads if that
gmap_shadow can already be used or if they have to retry.
Let's properly return errors using ERR_PTR() instead of simply returning
NULL, so a caller can properly react on the error.
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
arch/s390/include/asm/gmap.h | 2 ++
arch/s390/mm/gmap.c | 45 +++++++++++++++++++++++++++-----------------
2 files changed, 30 insertions(+), 17 deletions(-)
diff --git a/arch/s390/include/asm/gmap.h b/arch/s390/include/asm/gmap.h
index 4a47055..54a2487 100644
--- a/arch/s390/include/asm/gmap.h
+++ b/arch/s390/include/asm/gmap.h
@@ -27,6 +27,7 @@
* @parent: pointer to the parent gmap for shadow guest address spaces
* @orig_asce: ASCE for which the shadow page table has been created
* @removed: flag to indicate if a shadow guest address space has been removed
+ * @initialized: flag to indicate if a shadow guest address space can be used
*/
struct gmap {
struct list_head list;
@@ -49,6 +50,7 @@ struct gmap {
struct gmap *parent;
unsigned long orig_asce;
bool removed;
+ bool initialized;
};
/**
diff --git a/arch/s390/mm/gmap.c b/arch/s390/mm/gmap.c
index a396e58..a7dfb33 100644
--- a/arch/s390/mm/gmap.c
+++ b/arch/s390/mm/gmap.c
@@ -1384,7 +1384,8 @@ static void gmap_unshadow(struct gmap *sg)
* @asce: ASCE for which the shadow table is created
*
* Returns the pointer to a gmap if a shadow table with the given asce is
- * already available, otherwise NULL
+ * already available, ERR_PTR(-EAGAIN) if another one is just being created,
+ * otherwise NULL
*/
static struct gmap *gmap_find_shadow(struct gmap *parent, unsigned long asce)
{
@@ -1393,6 +1394,8 @@ static struct gmap *gmap_find_shadow(struct gmap *parent, unsigned long asce)
list_for_each_entry(sg, &parent->children, list) {
if (sg->orig_asce != asce || sg->removed)
continue;
+ if (!sg->initialized)
+ return ERR_PTR(-EAGAIN);
atomic_inc(&sg->ref_count);
return sg;
}
@@ -1409,8 +1412,9 @@ static struct gmap *gmap_find_shadow(struct gmap *parent, unsigned long asce)
* The shadow table will be removed automatically on any change to the
* PTE mapping for the source table.
*
- * Returns a guest address space structure, NULL if out of memory or if
- * anything goes wrong while protecting the top level pages.
+ * Returns a guest address space structure, ERR_PTR(-ENOMEM) if out of memory,
+ * ERR_PTR(-EAGAIN) if the caller has to retry and ERR_PTR(-EFAULT) if the
+ * parent gmap table could not be protected.
*/
struct gmap *gmap_shadow(struct gmap *parent, unsigned long asce)
{
@@ -1428,30 +1432,37 @@ struct gmap *gmap_shadow(struct gmap *parent, unsigned long asce)
limit = -1UL >> (33 - (((asce & _ASCE_TYPE_MASK) >> 2) * 11));
new = gmap_alloc(limit);
if (!new)
- return NULL;
+ return ERR_PTR(-ENOMEM);
new->mm = parent->mm;
new->parent = gmap_get(parent);
new->orig_asce = asce;
+ new->initialized = false;
+ spin_lock(&parent->shadow_lock);
+ /* Recheck if another CPU created the same shadow */
+ sg = gmap_find_shadow(parent, asce);
+ if (sg) {
+ spin_unlock(&parent->shadow_lock);
+ gmap_free(new);
+ return sg;
+ }
+ atomic_set(&new->ref_count, 2);
+ list_add(&new->list, &parent->children);
+ spin_unlock(&parent->shadow_lock);
+ /* protect after insertion, so it will get properly invalidated */
down_read(&parent->mm->mmap_sem);
rc = gmap_protect_range(parent, asce & _ASCE_ORIGIN,
((asce & _ASCE_TABLE_LENGTH) + 1) * 4096,
PROT_READ, PGSTE_VSIE_BIT);
up_read(&parent->mm->mmap_sem);
+ spin_lock(&parent->shadow_lock);
+ new->initialized = true;
if (rc) {
- atomic_set(&new->ref_count, 2);
- spin_lock(&parent->shadow_lock);
- /* Recheck if another CPU created the same shadow */
- sg = gmap_find_shadow(parent, asce);
- if (!sg) {
- list_add(&new->list, &parent->children);
- sg = new;
- new = NULL;
- }
- spin_unlock(&parent->shadow_lock);
- }
- if (new)
+ list_del(&new->list);
gmap_free(new);
- return sg;
+ new = ERR_PTR(rc);
+ }
+ spin_unlock(&parent->shadow_lock);
+ return new;
}
EXPORT_SYMBOL_GPL(gmap_shadow);
--
2.5.5
^ permalink raw reply related [flat|nested] 53+ messages in thread* [GIT PULL 11/51] s390/mm: take the mmap_sem in kvm_s390_shadow_fault()
2016-06-21 13:12 [GIT PULL 00/51] KVM: s390: vSIE (nested virtualization) feature for 4.8 (kvm/next) Christian Borntraeger
` (9 preceding siblings ...)
2016-06-21 13:12 ` [GIT PULL 10/51] s390/mm: fix races on gmap_shadow creation Christian Borntraeger
@ 2016-06-21 13:12 ` Christian Borntraeger
2016-06-21 13:12 ` [GIT PULL 12/51] s390/mm: protection exceptions are corrrectly shadowed Christian Borntraeger
` (40 subsequent siblings)
51 siblings, 0 replies; 53+ messages in thread
From: Christian Borntraeger @ 2016-06-21 13:12 UTC (permalink / raw)
To: Paolo Bonzini, Radim Krčmář
Cc: KVM, Cornelia Huck, linux-s390, Christian Borntraeger,
David Hildenbrand, Martin Schwidefsky
From: David Hildenbrand <dahi@linux.vnet.ibm.com>
Instead of doing it in the caller, let's just take the mmap_sem
in kvm_s390_shadow_fault(). By taking it as read, we allow parallel
faulting on shadow page tables, gmap shadow code is prepared for that.
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
arch/s390/kvm/gaccess.c | 32 +++++++++++++++-----------------
1 file changed, 15 insertions(+), 17 deletions(-)
diff --git a/arch/s390/kvm/gaccess.c b/arch/s390/kvm/gaccess.c
index c5f79c1..5b5eee2 100644
--- a/arch/s390/kvm/gaccess.c
+++ b/arch/s390/kvm/gaccess.c
@@ -1091,26 +1091,24 @@ int kvm_s390_shadow_fault(struct gmap *sg, unsigned long saddr, int write)
int dat_protection;
int rc;
+ down_read(&sg->mm->mmap_sem);
+
rc = gmap_shadow_pgt_lookup(sg, saddr, &pgt, &dat_protection);
- if (rc) {
+ if (rc)
rc = kvm_s390_shadow_tables(sg, saddr, &pgt, &dat_protection);
- if (rc)
- return rc;
- }
vaddr.addr = saddr;
- rc = gmap_read_table(sg->parent, pgt + vaddr.px * 8, &pte.val);
- if (rc)
- return rc;
- if (pte.i)
- return PGM_PAGE_TRANSLATION;
- if (pte.z || pte.co)
- return PGM_TRANSLATION_SPEC;
+ if (!rc)
+ rc = gmap_read_table(sg->parent, pgt + vaddr.px * 8, &pte.val);
+ if (!rc && pte.i)
+ rc = PGM_PAGE_TRANSLATION;
+ if (!rc && (pte.z || pte.co))
+ rc = PGM_TRANSLATION_SPEC;
dat_protection |= pte.p;
- if (write && dat_protection)
- return PGM_PROTECTION;
- rc = gmap_shadow_page(sg, saddr, __pte(pte.val));
- if (rc)
- return rc;
- return 0;
+ if (!rc && write && dat_protection)
+ rc = PGM_PROTECTION;
+ if (!rc)
+ rc = gmap_shadow_page(sg, saddr, __pte(pte.val));
+ up_read(&sg->mm->mmap_sem);
+ return rc;
}
--
2.5.5
^ permalink raw reply related [flat|nested] 53+ messages in thread* [GIT PULL 12/51] s390/mm: protection exceptions are corrrectly shadowed
2016-06-21 13:12 [GIT PULL 00/51] KVM: s390: vSIE (nested virtualization) feature for 4.8 (kvm/next) Christian Borntraeger
` (10 preceding siblings ...)
2016-06-21 13:12 ` [GIT PULL 11/51] s390/mm: take the mmap_sem in kvm_s390_shadow_fault() Christian Borntraeger
@ 2016-06-21 13:12 ` Christian Borntraeger
2016-06-21 13:12 ` [GIT PULL 13/51] s390/mm: take ipte_lock during shadow faults Christian Borntraeger
` (39 subsequent siblings)
51 siblings, 0 replies; 53+ messages in thread
From: Christian Borntraeger @ 2016-06-21 13:12 UTC (permalink / raw)
To: Paolo Bonzini, Radim Krčmář
Cc: KVM, Cornelia Huck, linux-s390, Christian Borntraeger,
David Hildenbrand, Martin Schwidefsky
From: David Hildenbrand <dahi@linux.vnet.ibm.com>
As gmap shadows contains correct protection permissions, protection
exceptons can directly be forwarded to guest 3. If we would encounter
a protection exception while faulting, the next guest 3 run will
automatically handle that for us.
Keep the dat_protection logic in place, as it will be helpful later.
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
arch/s390/kvm/gaccess.c | 6 +-----
arch/s390/kvm/gaccess.h | 2 +-
2 files changed, 2 insertions(+), 6 deletions(-)
diff --git a/arch/s390/kvm/gaccess.c b/arch/s390/kvm/gaccess.c
index 5b5eee2..b2783dd 100644
--- a/arch/s390/kvm/gaccess.c
+++ b/arch/s390/kvm/gaccess.c
@@ -1075,7 +1075,6 @@ static int kvm_s390_shadow_tables(struct gmap *sg, unsigned long saddr,
* kvm_s390_shadow_fault - handle fault on a shadow page table
* @sg: pointer to the shadow guest address space structure
* @saddr: faulting address in the shadow gmap
- * @write: =1 map r/w, =0 map r/o
*
* Returns: - 0 if the shadow fault was successfully resolved
* - > 0 (pgm exception code) on exceptions while faulting
@@ -1083,7 +1082,7 @@ static int kvm_s390_shadow_tables(struct gmap *sg, unsigned long saddr,
* - -EFAULT when accessing invalid guest addresses
* - -ENOMEM if out of memory
*/
-int kvm_s390_shadow_fault(struct gmap *sg, unsigned long saddr, int write)
+int kvm_s390_shadow_fault(struct gmap *sg, unsigned long saddr)
{
union vaddress vaddr;
union page_table_entry pte;
@@ -1104,9 +1103,6 @@ int kvm_s390_shadow_fault(struct gmap *sg, unsigned long saddr, int write)
rc = PGM_PAGE_TRANSLATION;
if (!rc && (pte.z || pte.co))
rc = PGM_TRANSLATION_SPEC;
- dat_protection |= pte.p;
- if (!rc && write && dat_protection)
- rc = PGM_PROTECTION;
if (!rc)
rc = gmap_shadow_page(sg, saddr, __pte(pte.val));
up_read(&sg->mm->mmap_sem);
diff --git a/arch/s390/kvm/gaccess.h b/arch/s390/kvm/gaccess.h
index e5ec473..0d044d0 100644
--- a/arch/s390/kvm/gaccess.h
+++ b/arch/s390/kvm/gaccess.h
@@ -361,6 +361,6 @@ void ipte_unlock(struct kvm_vcpu *vcpu);
int ipte_lock_held(struct kvm_vcpu *vcpu);
int kvm_s390_check_low_addr_prot_real(struct kvm_vcpu *vcpu, unsigned long gra);
-int kvm_s390_shadow_fault(struct gmap *shadow, unsigned long saddr, int write);
+int kvm_s390_shadow_fault(struct gmap *shadow, unsigned long saddr);
#endif /* __KVM_S390_GACCESS_H */
--
2.5.5
^ permalink raw reply related [flat|nested] 53+ messages in thread* [GIT PULL 13/51] s390/mm: take ipte_lock during shadow faults
2016-06-21 13:12 [GIT PULL 00/51] KVM: s390: vSIE (nested virtualization) feature for 4.8 (kvm/next) Christian Borntraeger
` (11 preceding siblings ...)
2016-06-21 13:12 ` [GIT PULL 12/51] s390/mm: protection exceptions are corrrectly shadowed Christian Borntraeger
@ 2016-06-21 13:12 ` Christian Borntraeger
2016-06-21 13:12 ` [GIT PULL 14/51] s390/mm: push ste protection down to shadow pte Christian Borntraeger
` (38 subsequent siblings)
51 siblings, 0 replies; 53+ messages in thread
From: Christian Borntraeger @ 2016-06-21 13:12 UTC (permalink / raw)
To: Paolo Bonzini, Radim Krčmář
Cc: KVM, Cornelia Huck, linux-s390, Christian Borntraeger,
David Hildenbrand, Martin Schwidefsky
From: David Hildenbrand <dahi@linux.vnet.ibm.com>
Let's take the ipte_lock while working on guest 2 provided page table, just
like the other gaccess functions.
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
arch/s390/kvm/gaccess.c | 11 ++++++++++-
arch/s390/kvm/gaccess.h | 3 ++-
2 files changed, 12 insertions(+), 2 deletions(-)
diff --git a/arch/s390/kvm/gaccess.c b/arch/s390/kvm/gaccess.c
index b2783dd..e70f916 100644
--- a/arch/s390/kvm/gaccess.c
+++ b/arch/s390/kvm/gaccess.c
@@ -1073,6 +1073,7 @@ static int kvm_s390_shadow_tables(struct gmap *sg, unsigned long saddr,
/**
* kvm_s390_shadow_fault - handle fault on a shadow page table
+ * @vcpu: virtual cpu
* @sg: pointer to the shadow guest address space structure
* @saddr: faulting address in the shadow gmap
*
@@ -1082,7 +1083,8 @@ static int kvm_s390_shadow_tables(struct gmap *sg, unsigned long saddr,
* - -EFAULT when accessing invalid guest addresses
* - -ENOMEM if out of memory
*/
-int kvm_s390_shadow_fault(struct gmap *sg, unsigned long saddr)
+int kvm_s390_shadow_fault(struct kvm_vcpu *vcpu, struct gmap *sg,
+ unsigned long saddr)
{
union vaddress vaddr;
union page_table_entry pte;
@@ -1091,6 +1093,12 @@ int kvm_s390_shadow_fault(struct gmap *sg, unsigned long saddr)
int rc;
down_read(&sg->mm->mmap_sem);
+ /*
+ * We don't want any guest-2 tables to change - so the parent
+ * tables/pointers we read stay valid - unshadowing is however
+ * always possible - only guest_table_lock protects us.
+ */
+ ipte_lock(vcpu);
rc = gmap_shadow_pgt_lookup(sg, saddr, &pgt, &dat_protection);
if (rc)
@@ -1105,6 +1113,7 @@ int kvm_s390_shadow_fault(struct gmap *sg, unsigned long saddr)
rc = PGM_TRANSLATION_SPEC;
if (!rc)
rc = gmap_shadow_page(sg, saddr, __pte(pte.val));
+ ipte_unlock(vcpu);
up_read(&sg->mm->mmap_sem);
return rc;
}
diff --git a/arch/s390/kvm/gaccess.h b/arch/s390/kvm/gaccess.h
index 0d044d0..8756569 100644
--- a/arch/s390/kvm/gaccess.h
+++ b/arch/s390/kvm/gaccess.h
@@ -361,6 +361,7 @@ void ipte_unlock(struct kvm_vcpu *vcpu);
int ipte_lock_held(struct kvm_vcpu *vcpu);
int kvm_s390_check_low_addr_prot_real(struct kvm_vcpu *vcpu, unsigned long gra);
-int kvm_s390_shadow_fault(struct gmap *shadow, unsigned long saddr);
+int kvm_s390_shadow_fault(struct kvm_vcpu *vcpu, struct gmap *shadow,
+ unsigned long saddr);
#endif /* __KVM_S390_GACCESS_H */
--
2.5.5
^ permalink raw reply related [flat|nested] 53+ messages in thread* [GIT PULL 14/51] s390/mm: push ste protection down to shadow pte
2016-06-21 13:12 [GIT PULL 00/51] KVM: s390: vSIE (nested virtualization) feature for 4.8 (kvm/next) Christian Borntraeger
` (12 preceding siblings ...)
2016-06-21 13:12 ` [GIT PULL 13/51] s390/mm: take ipte_lock during shadow faults Christian Borntraeger
@ 2016-06-21 13:12 ` Christian Borntraeger
2016-06-21 13:12 ` [GIT PULL 15/51] s390/mm: prepare for EDAT1/EDAT2 support in gmap shadow Christian Borntraeger
` (37 subsequent siblings)
51 siblings, 0 replies; 53+ messages in thread
From: Christian Borntraeger @ 2016-06-21 13:12 UTC (permalink / raw)
To: Paolo Bonzini, Radim Krčmář
Cc: KVM, Cornelia Huck, linux-s390, Christian Borntraeger,
David Hildenbrand, Martin Schwidefsky
From: David Hildenbrand <dahi@linux.vnet.ibm.com>
If a guest ste is read-only, it doesn't make sense to force the ptes in as
writable in the host. If the source page is read-only in the host, it won't
have to be made writable. Please note that if the source page is not
available, it will still be faulted in writable. This can be changed
internally later on.
If ste protection is removed, underlying shadow tables are also removed,
therefore this change does not affect the guest.
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
arch/s390/kvm/gaccess.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/arch/s390/kvm/gaccess.c b/arch/s390/kvm/gaccess.c
index e70f916..a85bc6c 100644
--- a/arch/s390/kvm/gaccess.c
+++ b/arch/s390/kvm/gaccess.c
@@ -1111,6 +1111,7 @@ int kvm_s390_shadow_fault(struct kvm_vcpu *vcpu, struct gmap *sg,
rc = PGM_PAGE_TRANSLATION;
if (!rc && (pte.z || pte.co))
rc = PGM_TRANSLATION_SPEC;
+ pte.p |= dat_protection;
if (!rc)
rc = gmap_shadow_page(sg, saddr, __pte(pte.val));
ipte_unlock(vcpu);
--
2.5.5
^ permalink raw reply related [flat|nested] 53+ messages in thread* [GIT PULL 15/51] s390/mm: prepare for EDAT1/EDAT2 support in gmap shadow
2016-06-21 13:12 [GIT PULL 00/51] KVM: s390: vSIE (nested virtualization) feature for 4.8 (kvm/next) Christian Borntraeger
` (13 preceding siblings ...)
2016-06-21 13:12 ` [GIT PULL 14/51] s390/mm: push ste protection down to shadow pte Christian Borntraeger
@ 2016-06-21 13:12 ` Christian Borntraeger
2016-06-21 13:12 ` [GIT PULL 16/51] s390/mm: support EDAT1 for gmap shadows Christian Borntraeger
` (36 subsequent siblings)
51 siblings, 0 replies; 53+ messages in thread
From: Christian Borntraeger @ 2016-06-21 13:12 UTC (permalink / raw)
To: Paolo Bonzini, Radim Krčmář
Cc: KVM, Cornelia Huck, linux-s390, Christian Borntraeger,
David Hildenbrand, Martin Schwidefsky
From: David Hildenbrand <dahi@linux.vnet.ibm.com>
In preparation for EDAT1/EDAT2 support for gmap shadows, we have to store
the requested edat level in the gmap shadow.
The edat level used during shadow translation is a property of the gmap
shadow. Depending on that level, the gmap shadow will look differently for
the same guest tables. We have to store it internally in order to support
it later.
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
arch/s390/include/asm/gmap.h | 5 ++++-
arch/s390/mm/gmap.c | 16 +++++++++++-----
2 files changed, 15 insertions(+), 6 deletions(-)
diff --git a/arch/s390/include/asm/gmap.h b/arch/s390/include/asm/gmap.h
index 54a2487..2ab397c 100644
--- a/arch/s390/include/asm/gmap.h
+++ b/arch/s390/include/asm/gmap.h
@@ -26,6 +26,7 @@
* @shadow_lock: spinlock to protect the shadow gmap list
* @parent: pointer to the parent gmap for shadow guest address spaces
* @orig_asce: ASCE for which the shadow page table has been created
+ * @edat_level: edat level to be used for the shadow translation
* @removed: flag to indicate if a shadow guest address space has been removed
* @initialized: flag to indicate if a shadow guest address space can be used
*/
@@ -49,6 +50,7 @@ struct gmap {
spinlock_t shadow_lock;
struct gmap *parent;
unsigned long orig_asce;
+ int edat_level;
bool removed;
bool initialized;
};
@@ -105,7 +107,8 @@ void gmap_unlink(struct mm_struct *, unsigned long *table, unsigned long vmaddr)
int gmap_read_table(struct gmap *gmap, unsigned long gaddr, unsigned long *val);
-struct gmap *gmap_shadow(struct gmap *parent, unsigned long asce);
+struct gmap *gmap_shadow(struct gmap *parent, unsigned long asce,
+ int edat_level);
int gmap_shadow_r2t(struct gmap *sg, unsigned long saddr, unsigned long r2t);
int gmap_shadow_r3t(struct gmap *sg, unsigned long saddr, unsigned long r3t);
int gmap_shadow_sgt(struct gmap *sg, unsigned long saddr, unsigned long sgt);
diff --git a/arch/s390/mm/gmap.c b/arch/s390/mm/gmap.c
index a7dfb33..f0b2a531 100644
--- a/arch/s390/mm/gmap.c
+++ b/arch/s390/mm/gmap.c
@@ -1382,17 +1382,20 @@ static void gmap_unshadow(struct gmap *sg)
* gmap_find_shadow - find a specific asce in the list of shadow tables
* @parent: pointer to the parent gmap
* @asce: ASCE for which the shadow table is created
+ * @edat_level: edat level to be used for the shadow translation
*
* Returns the pointer to a gmap if a shadow table with the given asce is
* already available, ERR_PTR(-EAGAIN) if another one is just being created,
* otherwise NULL
*/
-static struct gmap *gmap_find_shadow(struct gmap *parent, unsigned long asce)
+static struct gmap *gmap_find_shadow(struct gmap *parent, unsigned long asce,
+ int edat_level)
{
struct gmap *sg;
list_for_each_entry(sg, &parent->children, list) {
- if (sg->orig_asce != asce || sg->removed)
+ if (sg->orig_asce != asce || sg->edat_level != edat_level ||
+ sg->removed)
continue;
if (!sg->initialized)
return ERR_PTR(-EAGAIN);
@@ -1406,6 +1409,7 @@ static struct gmap *gmap_find_shadow(struct gmap *parent, unsigned long asce)
* gmap_shadow - create/find a shadow guest address space
* @parent: pointer to the parent gmap
* @asce: ASCE for which the shadow table is created
+ * @edat_level: edat level to be used for the shadow translation
*
* The pages of the top level page table referred by the asce parameter
* will be set to read-only and marked in the PGSTEs of the kvm process.
@@ -1416,7 +1420,8 @@ static struct gmap *gmap_find_shadow(struct gmap *parent, unsigned long asce)
* ERR_PTR(-EAGAIN) if the caller has to retry and ERR_PTR(-EFAULT) if the
* parent gmap table could not be protected.
*/
-struct gmap *gmap_shadow(struct gmap *parent, unsigned long asce)
+struct gmap *gmap_shadow(struct gmap *parent, unsigned long asce,
+ int edat_level)
{
struct gmap *sg, *new;
unsigned long limit;
@@ -1424,7 +1429,7 @@ struct gmap *gmap_shadow(struct gmap *parent, unsigned long asce)
BUG_ON(gmap_is_shadow(parent));
spin_lock(&parent->shadow_lock);
- sg = gmap_find_shadow(parent, asce);
+ sg = gmap_find_shadow(parent, asce, edat_level);
spin_unlock(&parent->shadow_lock);
if (sg)
return sg;
@@ -1436,10 +1441,11 @@ struct gmap *gmap_shadow(struct gmap *parent, unsigned long asce)
new->mm = parent->mm;
new->parent = gmap_get(parent);
new->orig_asce = asce;
+ new->edat_level = edat_level;
new->initialized = false;
spin_lock(&parent->shadow_lock);
/* Recheck if another CPU created the same shadow */
- sg = gmap_find_shadow(parent, asce);
+ sg = gmap_find_shadow(parent, asce, edat_level);
if (sg) {
spin_unlock(&parent->shadow_lock);
gmap_free(new);
--
2.5.5
^ permalink raw reply related [flat|nested] 53+ messages in thread* [GIT PULL 16/51] s390/mm: support EDAT1 for gmap shadows
2016-06-21 13:12 [GIT PULL 00/51] KVM: s390: vSIE (nested virtualization) feature for 4.8 (kvm/next) Christian Borntraeger
` (14 preceding siblings ...)
2016-06-21 13:12 ` [GIT PULL 15/51] s390/mm: prepare for EDAT1/EDAT2 support in gmap shadow Christian Borntraeger
@ 2016-06-21 13:12 ` Christian Borntraeger
2016-06-21 13:12 ` [GIT PULL 17/51] s390/mm: support EDAT2 " Christian Borntraeger
` (35 subsequent siblings)
51 siblings, 0 replies; 53+ messages in thread
From: Christian Borntraeger @ 2016-06-21 13:12 UTC (permalink / raw)
To: Paolo Bonzini, Radim Krčmář
Cc: KVM, Cornelia Huck, linux-s390, Christian Borntraeger,
David Hildenbrand, Martin Schwidefsky
From: David Hildenbrand <dahi@linux.vnet.ibm.com>
If the guest is enabled for EDAT1, we can easily create shadows for
guest2 -> guest3 provided tables that make use of EDAT1.
If guest2 references a 1MB page, this memory looks consecutive for guest2,
but it might not be so for us. Therefore we have to create fake page tables.
We can easily add that to our existing infrastructure. The invalidation
mechanism will make sure that fake page tables are removed when the parent
table (sgt table entry) is changed.
As EDAT1 also introduced protection on all page table levels, we have to
also shadow these correctly.
We don't have to care about:
- ACCF-Validity Control in STE
- Access-Control Bits in STE
- Fetch-Protection Bit in STE
- Common-Segment Bit in STE
As all bits might be dropped and there is no guaranteed that they are
active ("unpredictable whether the CPU uses these bits", "may be used").
Without using EDAT1 in the shadow ourselfes (STE-format control == 0),
simply shadowing these bits would not be enough. They would be ignored.
Please note that we are using the "fake" flag to make this look consistent
with further changes (EDAT2, real-space designation support) and don't let
the shadow functions handle fc=1 stes.
In the future, with huge pages in the host, gmap_shadow_pgt() could simply
try to map a huge host page if "fake" is set to one and indicate via return
value that no lower fake tables / shadow ptes are required.
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
arch/s390/include/asm/gmap.h | 5 +++--
arch/s390/kvm/gaccess.c | 34 +++++++++++++++++++++++++++-------
arch/s390/mm/gmap.c | 29 +++++++++++++++++++++++++----
3 files changed, 55 insertions(+), 13 deletions(-)
diff --git a/arch/s390/include/asm/gmap.h b/arch/s390/include/asm/gmap.h
index 2ab397c..c8ba5a1 100644
--- a/arch/s390/include/asm/gmap.h
+++ b/arch/s390/include/asm/gmap.h
@@ -112,9 +112,10 @@ struct gmap *gmap_shadow(struct gmap *parent, unsigned long asce,
int gmap_shadow_r2t(struct gmap *sg, unsigned long saddr, unsigned long r2t);
int gmap_shadow_r3t(struct gmap *sg, unsigned long saddr, unsigned long r3t);
int gmap_shadow_sgt(struct gmap *sg, unsigned long saddr, unsigned long sgt);
-int gmap_shadow_pgt(struct gmap *sg, unsigned long saddr, unsigned long pgt);
+int gmap_shadow_pgt(struct gmap *sg, unsigned long saddr, unsigned long pgt,
+ int fake);
int gmap_shadow_pgt_lookup(struct gmap *sg, unsigned long saddr,
- unsigned long *pgt, int *dat_protection);
+ unsigned long *pgt, int *dat_protection, int *fake);
int gmap_shadow_page(struct gmap *sg, unsigned long saddr, pte_t pte);
void gmap_register_pte_notifier(struct gmap_notifier *);
diff --git a/arch/s390/kvm/gaccess.c b/arch/s390/kvm/gaccess.c
index a85bc6c..af1fc6f 100644
--- a/arch/s390/kvm/gaccess.c
+++ b/arch/s390/kvm/gaccess.c
@@ -953,9 +953,11 @@ int kvm_s390_check_low_addr_prot_real(struct kvm_vcpu *vcpu, unsigned long gra)
* @sg: pointer to the shadow guest address space structure
* @saddr: faulting address in the shadow gmap
* @pgt: pointer to the page table address result
+ * @fake: pgt references contiguous guest memory block, not a pgtable
*/
static int kvm_s390_shadow_tables(struct gmap *sg, unsigned long saddr,
- unsigned long *pgt, int *dat_protection)
+ unsigned long *pgt, int *dat_protection,
+ int *fake)
{
struct gmap *parent;
union asce asce;
@@ -963,6 +965,7 @@ static int kvm_s390_shadow_tables(struct gmap *sg, unsigned long saddr,
unsigned long ptr;
int rc;
+ *fake = 0;
parent = sg->parent;
vaddr.addr = saddr;
asce.val = sg->orig_asce;
@@ -1060,10 +1063,20 @@ static int kvm_s390_shadow_tables(struct gmap *sg, unsigned long saddr,
if (ste.cs && asce.p)
return PGM_TRANSLATION_SPEC;
*dat_protection = ste.fc0.p;
- rc = gmap_shadow_pgt(sg, saddr, ste.val);
+ if (ste.fc && sg->edat_level >= 1) {
+ bool prot = ste.fc1.p;
+
+ *fake = 1;
+ ptr = ste.fc1.sfaa << 20UL;
+ ste.val = ptr;
+ ste.fc0.p = prot;
+ goto shadow_pgt;
+ }
+ ptr = ste.fc0.pto << 11UL;
+shadow_pgt:
+ rc = gmap_shadow_pgt(sg, saddr, ste.val, *fake);
if (rc)
return rc;
- ptr = ste.fc0.pto * 2048;
}
}
/* Return the parent address of the page table */
@@ -1089,7 +1102,7 @@ int kvm_s390_shadow_fault(struct kvm_vcpu *vcpu, struct gmap *sg,
union vaddress vaddr;
union page_table_entry pte;
unsigned long pgt;
- int dat_protection;
+ int dat_protection, fake;
int rc;
down_read(&sg->mm->mmap_sem);
@@ -1100,17 +1113,24 @@ int kvm_s390_shadow_fault(struct kvm_vcpu *vcpu, struct gmap *sg,
*/
ipte_lock(vcpu);
- rc = gmap_shadow_pgt_lookup(sg, saddr, &pgt, &dat_protection);
+ rc = gmap_shadow_pgt_lookup(sg, saddr, &pgt, &dat_protection, &fake);
if (rc)
- rc = kvm_s390_shadow_tables(sg, saddr, &pgt, &dat_protection);
+ rc = kvm_s390_shadow_tables(sg, saddr, &pgt, &dat_protection,
+ &fake);
vaddr.addr = saddr;
+ if (fake) {
+ /* offset in 1MB guest memory block */
+ pte.val = pgt + ((unsigned long) vaddr.px << 12UL);
+ goto shadow_page;
+ }
if (!rc)
rc = gmap_read_table(sg->parent, pgt + vaddr.px * 8, &pte.val);
if (!rc && pte.i)
rc = PGM_PAGE_TRANSLATION;
- if (!rc && (pte.z || pte.co))
+ if (!rc && (pte.z || (pte.co && sg->edat_level < 1)))
rc = PGM_TRANSLATION_SPEC;
+shadow_page:
pte.p |= dat_protection;
if (!rc)
rc = gmap_shadow_page(sg, saddr, __pte(pte.val));
diff --git a/arch/s390/mm/gmap.c b/arch/s390/mm/gmap.c
index f0b2a531..de7ad7b 100644
--- a/arch/s390/mm/gmap.c
+++ b/arch/s390/mm/gmap.c
@@ -20,6 +20,8 @@
#include <asm/gmap.h>
#include <asm/tlb.h>
+#define GMAP_SHADOW_FAKE_TABLE 1ULL
+
/**
* gmap_alloc - allocate and initialize a guest address space
* @mm: pointer to the parent mm_struct
@@ -1521,6 +1523,8 @@ int gmap_shadow_r2t(struct gmap *sg, unsigned long saddr, unsigned long r2t)
/* mark as invalid as long as the parent table is not protected */
*table = (unsigned long) s_r2t | _REGION_ENTRY_LENGTH |
_REGION_ENTRY_TYPE_R1 | _REGION_ENTRY_INVALID;
+ if (sg->edat_level >= 1)
+ *table |= (r2t & _REGION_ENTRY_PROTECT);
list_add(&page->lru, &sg->crst_list);
spin_unlock(&sg->guest_table_lock);
/* Make r2t read-only in parent gmap page table */
@@ -1592,6 +1596,8 @@ int gmap_shadow_r3t(struct gmap *sg, unsigned long saddr, unsigned long r3t)
/* mark as invalid as long as the parent table is not protected */
*table = (unsigned long) s_r3t | _REGION_ENTRY_LENGTH |
_REGION_ENTRY_TYPE_R2 | _REGION_ENTRY_INVALID;
+ if (sg->edat_level >= 1)
+ *table |= (r3t & _REGION_ENTRY_PROTECT);
list_add(&page->lru, &sg->crst_list);
spin_unlock(&sg->guest_table_lock);
/* Make r3t read-only in parent gmap page table */
@@ -1664,6 +1670,8 @@ int gmap_shadow_sgt(struct gmap *sg, unsigned long saddr, unsigned long sgt)
/* mark as invalid as long as the parent table is not protected */
*table = (unsigned long) s_sgt | _REGION_ENTRY_LENGTH |
_REGION_ENTRY_TYPE_R3 | _REGION_ENTRY_INVALID;
+ if (sg->edat_level >= 1)
+ *table |= sgt & _REGION_ENTRY_PROTECT;
list_add(&page->lru, &sg->crst_list);
spin_unlock(&sg->guest_table_lock);
/* Make sgt read-only in parent gmap page table */
@@ -1698,6 +1706,7 @@ EXPORT_SYMBOL_GPL(gmap_shadow_sgt);
* @saddr: the address in the shadow aguest address space
* @pgt: parent gmap address of the page table to get shadowed
* @dat_protection: if the pgtable is marked as protected by dat
+ * @fake: pgt references contiguous guest memory block, not a pgtable
*
* Returns 0 if the shadow page table was found and -EAGAIN if the page
* table was not found.
@@ -1705,7 +1714,8 @@ EXPORT_SYMBOL_GPL(gmap_shadow_sgt);
* Called with sg->mm->mmap_sem in read.
*/
int gmap_shadow_pgt_lookup(struct gmap *sg, unsigned long saddr,
- unsigned long *pgt, int *dat_protection)
+ unsigned long *pgt, int *dat_protection,
+ int *fake)
{
unsigned long *table;
struct page *page;
@@ -1717,8 +1727,9 @@ int gmap_shadow_pgt_lookup(struct gmap *sg, unsigned long saddr,
if (table && !(*table & _SEGMENT_ENTRY_INVALID)) {
/* Shadow page tables are full pages (pte+pgste) */
page = pfn_to_page(*table >> PAGE_SHIFT);
- *pgt = page->index;
+ *pgt = page->index & ~GMAP_SHADOW_FAKE_TABLE;
*dat_protection = !!(*table & _SEGMENT_ENTRY_PROTECT);
+ *fake = !!(page->index & GMAP_SHADOW_FAKE_TABLE);
rc = 0;
} else {
rc = -EAGAIN;
@@ -1734,6 +1745,7 @@ EXPORT_SYMBOL_GPL(gmap_shadow_pgt_lookup);
* @sg: pointer to the shadow guest address space structure
* @saddr: faulting address in the shadow gmap
* @pgt: parent gmap address of the page table to get shadowed
+ * @fake: pgt references contiguous guest memory block, not a pgtable
*
* Returns 0 if successfully shadowed or already shadowed, -EAGAIN if the
* shadow table structure is incomplete, -ENOMEM if out of memory,
@@ -1741,19 +1753,22 @@ EXPORT_SYMBOL_GPL(gmap_shadow_pgt_lookup);
*
* Called with gmap->mm->mmap_sem in read
*/
-int gmap_shadow_pgt(struct gmap *sg, unsigned long saddr, unsigned long pgt)
+int gmap_shadow_pgt(struct gmap *sg, unsigned long saddr, unsigned long pgt,
+ int fake)
{
unsigned long raddr, origin;
unsigned long *s_pgt, *table;
struct page *page;
int rc;
- BUG_ON(!gmap_is_shadow(sg));
+ BUG_ON(!gmap_is_shadow(sg) || (pgt & _SEGMENT_ENTRY_LARGE));
/* Allocate a shadow page table */
page = page_table_alloc_pgste(sg->mm);
if (!page)
return -ENOMEM;
page->index = pgt & _SEGMENT_ENTRY_ORIGIN;
+ if (fake)
+ page->index |= GMAP_SHADOW_FAKE_TABLE;
s_pgt = (unsigned long *) page_to_phys(page);
/* Install shadow page table */
spin_lock(&sg->guest_table_lock);
@@ -1773,6 +1788,12 @@ int gmap_shadow_pgt(struct gmap *sg, unsigned long saddr, unsigned long pgt)
*table = (unsigned long) s_pgt | _SEGMENT_ENTRY |
(pgt & _SEGMENT_ENTRY_PROTECT) | _SEGMENT_ENTRY_INVALID;
list_add(&page->lru, &sg->pt_list);
+ if (fake) {
+ /* nothing to protect for fake tables */
+ *table &= ~_SEGMENT_ENTRY_INVALID;
+ spin_unlock(&sg->guest_table_lock);
+ return 0;
+ }
spin_unlock(&sg->guest_table_lock);
/* Make pgt read-only in parent gmap page table (not the pgste) */
raddr = (saddr & 0xfffffffffff00000UL) | _SHADOW_RMAP_SEGMENT;
--
2.5.5
^ permalink raw reply related [flat|nested] 53+ messages in thread* [GIT PULL 17/51] s390/mm: support EDAT2 for gmap shadows
2016-06-21 13:12 [GIT PULL 00/51] KVM: s390: vSIE (nested virtualization) feature for 4.8 (kvm/next) Christian Borntraeger
` (15 preceding siblings ...)
2016-06-21 13:12 ` [GIT PULL 16/51] s390/mm: support EDAT1 for gmap shadows Christian Borntraeger
@ 2016-06-21 13:12 ` Christian Borntraeger
2016-06-21 13:12 ` [GIT PULL 18/51] s390/mm: push rte protection down to shadow pte Christian Borntraeger
` (34 subsequent siblings)
51 siblings, 0 replies; 53+ messages in thread
From: Christian Borntraeger @ 2016-06-21 13:12 UTC (permalink / raw)
To: Paolo Bonzini, Radim Krčmář
Cc: KVM, Cornelia Huck, linux-s390, Christian Borntraeger,
David Hildenbrand, Martin Schwidefsky
From: David Hildenbrand <dahi@linux.vnet.ibm.com>
If the guest is enabled for EDAT2, we can easily create shadows for
guest2 -> guest3 provided tables that make use of EDAT2.
If guest2 references a 2GB page, this memory looks consecutive for guest2,
but it does not have to be so for us. Therefore we have to create fake
segment and page tables.
This works just like EDAT1 support, so page tables are removed when the
parent table (r3t table entry) is changed.
We don't hve to care about:
- ACCF-Validity Control in RTTE
- Access-Control Bits in RTTE
- Fetch-Protection Bit in RTTE
- Common-Region Bit in RTTE
Just like for EDAT1, all bits might be dropped and there is no guaranteed
that they are active.
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
arch/s390/include/asm/gmap.h | 3 ++-
arch/s390/kvm/gaccess.c | 22 ++++++++++++++++++++--
arch/s390/mm/gmap.c | 14 ++++++++++++--
3 files changed, 34 insertions(+), 5 deletions(-)
diff --git a/arch/s390/include/asm/gmap.h b/arch/s390/include/asm/gmap.h
index c8ba5a1..2e4c3b2 100644
--- a/arch/s390/include/asm/gmap.h
+++ b/arch/s390/include/asm/gmap.h
@@ -111,7 +111,8 @@ struct gmap *gmap_shadow(struct gmap *parent, unsigned long asce,
int edat_level);
int gmap_shadow_r2t(struct gmap *sg, unsigned long saddr, unsigned long r2t);
int gmap_shadow_r3t(struct gmap *sg, unsigned long saddr, unsigned long r3t);
-int gmap_shadow_sgt(struct gmap *sg, unsigned long saddr, unsigned long sgt);
+int gmap_shadow_sgt(struct gmap *sg, unsigned long saddr, unsigned long sgt,
+ int fake);
int gmap_shadow_pgt(struct gmap *sg, unsigned long saddr, unsigned long pgt,
int fake);
int gmap_shadow_pgt_lookup(struct gmap *sg, unsigned long saddr,
diff --git a/arch/s390/kvm/gaccess.c b/arch/s390/kvm/gaccess.c
index af1fc6f..fab03ec 100644
--- a/arch/s390/kvm/gaccess.c
+++ b/arch/s390/kvm/gaccess.c
@@ -1042,17 +1042,35 @@ static int kvm_s390_shadow_tables(struct gmap *sg, unsigned long saddr,
return PGM_REGION_THIRD_TRANS;
if (rtte.tt != TABLE_TYPE_REGION3)
return PGM_TRANSLATION_SPEC;
+ if (rtte.cr && asce.p && sg->edat_level >= 2)
+ return PGM_TRANSLATION_SPEC;
+ if (rtte.fc && sg->edat_level >= 2) {
+ bool prot = rtte.fc1.p;
+
+ *fake = 1;
+ ptr = rtte.fc1.rfaa << 31UL;
+ rtte.val = ptr;
+ rtte.fc0.p = prot;
+ goto shadow_sgt;
+ }
if (vaddr.sx01 < rtte.fc0.tf || vaddr.sx01 > rtte.fc0.tl)
return PGM_SEGMENT_TRANSLATION;
- rc = gmap_shadow_sgt(sg, saddr, rtte.val);
+ ptr = rtte.fc0.sto << 12UL;
+shadow_sgt:
+ rc = gmap_shadow_sgt(sg, saddr, rtte.val, *fake);
if (rc)
return rc;
- ptr = rtte.fc0.sto * 4096;
/* fallthrough */
}
case ASCE_TYPE_SEGMENT: {
union segment_table_entry ste;
+ if (*fake) {
+ /* offset in 2G guest memory block */
+ ptr = ptr + ((unsigned long) vaddr.sx << 20UL);
+ ste.val = ptr;
+ goto shadow_pgt;
+ }
rc = gmap_read_table(parent, ptr + vaddr.sx * 8, &ste.val);
if (rc)
return rc;
diff --git a/arch/s390/mm/gmap.c b/arch/s390/mm/gmap.c
index de7ad7b..c96bf30 100644
--- a/arch/s390/mm/gmap.c
+++ b/arch/s390/mm/gmap.c
@@ -1631,6 +1631,7 @@ EXPORT_SYMBOL_GPL(gmap_shadow_r3t);
* @sg: pointer to the shadow guest address space structure
* @saddr: faulting address in the shadow gmap
* @sgt: parent gmap address of the segment table to get shadowed
+ * @fake: sgt references contiguous guest memory block, not a sgt
*
* Returns: 0 if successfully shadowed or already shadowed, -EAGAIN if the
* shadow table structure is incomplete, -ENOMEM if out of memory and
@@ -1638,19 +1639,22 @@ EXPORT_SYMBOL_GPL(gmap_shadow_r3t);
*
* Called with sg->mm->mmap_sem in read.
*/
-int gmap_shadow_sgt(struct gmap *sg, unsigned long saddr, unsigned long sgt)
+int gmap_shadow_sgt(struct gmap *sg, unsigned long saddr, unsigned long sgt,
+ int fake)
{
unsigned long raddr, origin, offset, len;
unsigned long *s_sgt, *table;
struct page *page;
int rc;
- BUG_ON(!gmap_is_shadow(sg));
+ BUG_ON(!gmap_is_shadow(sg) || (sgt & _REGION3_ENTRY_LARGE));
/* Allocate a shadow segment table */
page = alloc_pages(GFP_KERNEL, 2);
if (!page)
return -ENOMEM;
page->index = sgt & _REGION_ENTRY_ORIGIN;
+ if (fake)
+ page->index |= GMAP_SHADOW_FAKE_TABLE;
s_sgt = (unsigned long *) page_to_phys(page);
/* Install shadow region second table */
spin_lock(&sg->guest_table_lock);
@@ -1673,6 +1677,12 @@ int gmap_shadow_sgt(struct gmap *sg, unsigned long saddr, unsigned long sgt)
if (sg->edat_level >= 1)
*table |= sgt & _REGION_ENTRY_PROTECT;
list_add(&page->lru, &sg->crst_list);
+ if (fake) {
+ /* nothing to protect for fake tables */
+ *table &= ~_REGION_ENTRY_INVALID;
+ spin_unlock(&sg->guest_table_lock);
+ return 0;
+ }
spin_unlock(&sg->guest_table_lock);
/* Make sgt read-only in parent gmap page table */
raddr = (saddr & 0xffffffff80000000UL) | _SHADOW_RMAP_REGION3;
--
2.5.5
^ permalink raw reply related [flat|nested] 53+ messages in thread* [GIT PULL 18/51] s390/mm: push rte protection down to shadow pte
2016-06-21 13:12 [GIT PULL 00/51] KVM: s390: vSIE (nested virtualization) feature for 4.8 (kvm/next) Christian Borntraeger
` (16 preceding siblings ...)
2016-06-21 13:12 ` [GIT PULL 17/51] s390/mm: support EDAT2 " Christian Borntraeger
@ 2016-06-21 13:12 ` Christian Borntraeger
2016-06-21 13:12 ` [GIT PULL 19/51] s390/mm: support real-space for gmap shadows Christian Borntraeger
` (33 subsequent siblings)
51 siblings, 0 replies; 53+ messages in thread
From: Christian Borntraeger @ 2016-06-21 13:12 UTC (permalink / raw)
To: Paolo Bonzini, Radim Krčmář
Cc: KVM, Cornelia Huck, linux-s390, Christian Borntraeger,
David Hildenbrand, Martin Schwidefsky
From: David Hildenbrand <dahi@linux.vnet.ibm.com>
Just like we already do with ste protection, let's take rte protection
into account. This way, the host pte doesn't have to be mapped writable.
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
arch/s390/kvm/gaccess.c | 19 ++++++++++++-------
1 file changed, 12 insertions(+), 7 deletions(-)
diff --git a/arch/s390/kvm/gaccess.c b/arch/s390/kvm/gaccess.c
index fab03ec..f6d556d 100644
--- a/arch/s390/kvm/gaccess.c
+++ b/arch/s390/kvm/gaccess.c
@@ -966,6 +966,7 @@ static int kvm_s390_shadow_tables(struct gmap *sg, unsigned long saddr,
int rc;
*fake = 0;
+ *dat_protection = 0;
parent = sg->parent;
vaddr.addr = saddr;
asce.val = sg->orig_asce;
@@ -1008,6 +1009,8 @@ static int kvm_s390_shadow_tables(struct gmap *sg, unsigned long saddr,
return PGM_TRANSLATION_SPEC;
if (vaddr.rsx01 < rfte.tf || vaddr.rsx01 > rfte.tl)
return PGM_REGION_SECOND_TRANS;
+ if (sg->edat_level >= 1)
+ *dat_protection |= rfte.p;
rc = gmap_shadow_r2t(sg, saddr, rfte.val);
if (rc)
return rc;
@@ -1026,6 +1029,9 @@ static int kvm_s390_shadow_tables(struct gmap *sg, unsigned long saddr,
return PGM_TRANSLATION_SPEC;
if (vaddr.rtx01 < rste.tf || vaddr.rtx01 > rste.tl)
return PGM_REGION_THIRD_TRANS;
+ if (sg->edat_level >= 1)
+ *dat_protection |= rste.p;
+ rste.p |= *dat_protection;
rc = gmap_shadow_r3t(sg, saddr, rste.val);
if (rc)
return rc;
@@ -1045,18 +1051,19 @@ static int kvm_s390_shadow_tables(struct gmap *sg, unsigned long saddr,
if (rtte.cr && asce.p && sg->edat_level >= 2)
return PGM_TRANSLATION_SPEC;
if (rtte.fc && sg->edat_level >= 2) {
- bool prot = rtte.fc1.p;
-
+ *dat_protection |= rtte.fc0.p;
*fake = 1;
ptr = rtte.fc1.rfaa << 31UL;
rtte.val = ptr;
- rtte.fc0.p = prot;
goto shadow_sgt;
}
if (vaddr.sx01 < rtte.fc0.tf || vaddr.sx01 > rtte.fc0.tl)
return PGM_SEGMENT_TRANSLATION;
+ if (sg->edat_level >= 1)
+ *dat_protection |= rtte.fc0.p;
ptr = rtte.fc0.sto << 12UL;
shadow_sgt:
+ rtte.fc0.p |= *dat_protection;
rc = gmap_shadow_sgt(sg, saddr, rtte.val, *fake);
if (rc)
return rc;
@@ -1080,18 +1087,16 @@ shadow_sgt:
return PGM_TRANSLATION_SPEC;
if (ste.cs && asce.p)
return PGM_TRANSLATION_SPEC;
- *dat_protection = ste.fc0.p;
+ *dat_protection |= ste.fc0.p;
if (ste.fc && sg->edat_level >= 1) {
- bool prot = ste.fc1.p;
-
*fake = 1;
ptr = ste.fc1.sfaa << 20UL;
ste.val = ptr;
- ste.fc0.p = prot;
goto shadow_pgt;
}
ptr = ste.fc0.pto << 11UL;
shadow_pgt:
+ ste.fc0.p |= *dat_protection;
rc = gmap_shadow_pgt(sg, saddr, ste.val, *fake);
if (rc)
return rc;
--
2.5.5
^ permalink raw reply related [flat|nested] 53+ messages in thread* [GIT PULL 19/51] s390/mm: support real-space for gmap shadows
2016-06-21 13:12 [GIT PULL 00/51] KVM: s390: vSIE (nested virtualization) feature for 4.8 (kvm/next) Christian Borntraeger
` (17 preceding siblings ...)
2016-06-21 13:12 ` [GIT PULL 18/51] s390/mm: push rte protection down to shadow pte Christian Borntraeger
@ 2016-06-21 13:12 ` Christian Borntraeger
2016-06-21 13:12 ` [GIT PULL 20/51] s390/mm: limit number of real-space " Christian Borntraeger
` (32 subsequent siblings)
51 siblings, 0 replies; 53+ messages in thread
From: Christian Borntraeger @ 2016-06-21 13:12 UTC (permalink / raw)
To: Paolo Bonzini, Radim Krčmář
Cc: KVM, Cornelia Huck, linux-s390, Christian Borntraeger,
David Hildenbrand, Martin Schwidefsky
From: David Hildenbrand <dahi@linux.vnet.ibm.com>
We can easily support real-space designation just like EDAT1 and EDAT2.
So guest2 can provide for guest3 an asce with the real-space control being
set.
We simply have to allocate the biggest page table possible and fake all
levels.
There is no protection to consider. If we exceed guest memory, vsie code
will inject an addressing exception (via program intercept). In the future,
we could limit the fake table level to the gmap page table.
As the top level page table can never go away, such gmap shadows will never
get unshadowed, we'll have to come up with another way to limit the number
of kept gmap shadows.
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
arch/s390/include/asm/gmap.h | 6 ++++--
arch/s390/kvm/gaccess.c | 34 +++++++++++++++++++++++++++++-----
arch/s390/mm/gmap.c | 35 ++++++++++++++++++++++++++++++++---
3 files changed, 65 insertions(+), 10 deletions(-)
diff --git a/arch/s390/include/asm/gmap.h b/arch/s390/include/asm/gmap.h
index 2e4c3b2..752cf47 100644
--- a/arch/s390/include/asm/gmap.h
+++ b/arch/s390/include/asm/gmap.h
@@ -109,8 +109,10 @@ int gmap_read_table(struct gmap *gmap, unsigned long gaddr, unsigned long *val);
struct gmap *gmap_shadow(struct gmap *parent, unsigned long asce,
int edat_level);
-int gmap_shadow_r2t(struct gmap *sg, unsigned long saddr, unsigned long r2t);
-int gmap_shadow_r3t(struct gmap *sg, unsigned long saddr, unsigned long r3t);
+int gmap_shadow_r2t(struct gmap *sg, unsigned long saddr, unsigned long r2t,
+ int fake);
+int gmap_shadow_r3t(struct gmap *sg, unsigned long saddr, unsigned long r3t,
+ int fake);
int gmap_shadow_sgt(struct gmap *sg, unsigned long saddr, unsigned long sgt,
int fake);
int gmap_shadow_pgt(struct gmap *sg, unsigned long saddr, unsigned long pgt,
diff --git a/arch/s390/kvm/gaccess.c b/arch/s390/kvm/gaccess.c
index f6d556d..5420020 100644
--- a/arch/s390/kvm/gaccess.c
+++ b/arch/s390/kvm/gaccess.c
@@ -971,9 +971,13 @@ static int kvm_s390_shadow_tables(struct gmap *sg, unsigned long saddr,
vaddr.addr = saddr;
asce.val = sg->orig_asce;
ptr = asce.origin * 4096;
+ if (asce.r) {
+ *fake = 1;
+ asce.dt = ASCE_TYPE_REGION1;
+ }
switch (asce.dt) {
case ASCE_TYPE_REGION1:
- if (vaddr.rfx01 > asce.tl)
+ if (vaddr.rfx01 > asce.tl && !asce.r)
return PGM_REGION_FIRST_TRANS;
break;
case ASCE_TYPE_REGION2:
@@ -1000,6 +1004,12 @@ static int kvm_s390_shadow_tables(struct gmap *sg, unsigned long saddr,
case ASCE_TYPE_REGION1: {
union region1_table_entry rfte;
+ if (*fake) {
+ /* offset in 16EB guest memory block */
+ ptr = ptr + ((unsigned long) vaddr.rsx << 53UL);
+ rfte.val = ptr;
+ goto shadow_r2t;
+ }
rc = gmap_read_table(parent, ptr + vaddr.rfx * 8, &rfte.val);
if (rc)
return rc;
@@ -1011,15 +1021,22 @@ static int kvm_s390_shadow_tables(struct gmap *sg, unsigned long saddr,
return PGM_REGION_SECOND_TRANS;
if (sg->edat_level >= 1)
*dat_protection |= rfte.p;
- rc = gmap_shadow_r2t(sg, saddr, rfte.val);
+ ptr = rfte.rto << 12UL;
+shadow_r2t:
+ rc = gmap_shadow_r2t(sg, saddr, rfte.val, *fake);
if (rc)
return rc;
- ptr = rfte.rto * 4096;
/* fallthrough */
}
case ASCE_TYPE_REGION2: {
union region2_table_entry rste;
+ if (*fake) {
+ /* offset in 8PB guest memory block */
+ ptr = ptr + ((unsigned long) vaddr.rtx << 42UL);
+ rste.val = ptr;
+ goto shadow_r3t;
+ }
rc = gmap_read_table(parent, ptr + vaddr.rsx * 8, &rste.val);
if (rc)
return rc;
@@ -1031,16 +1048,23 @@ static int kvm_s390_shadow_tables(struct gmap *sg, unsigned long saddr,
return PGM_REGION_THIRD_TRANS;
if (sg->edat_level >= 1)
*dat_protection |= rste.p;
+ ptr = rste.rto << 12UL;
+shadow_r3t:
rste.p |= *dat_protection;
- rc = gmap_shadow_r3t(sg, saddr, rste.val);
+ rc = gmap_shadow_r3t(sg, saddr, rste.val, *fake);
if (rc)
return rc;
- ptr = rste.rto * 4096;
/* fallthrough */
}
case ASCE_TYPE_REGION3: {
union region3_table_entry rtte;
+ if (*fake) {
+ /* offset in 4TB guest memory block */
+ ptr = ptr + ((unsigned long) vaddr.sx << 31UL);
+ rtte.val = ptr;
+ goto shadow_sgt;
+ }
rc = gmap_read_table(parent, ptr + vaddr.rtx * 8, &rtte.val);
if (rc)
return rc;
diff --git a/arch/s390/mm/gmap.c b/arch/s390/mm/gmap.c
index c96bf30..c07d64f 100644
--- a/arch/s390/mm/gmap.c
+++ b/arch/s390/mm/gmap.c
@@ -1437,6 +1437,8 @@ struct gmap *gmap_shadow(struct gmap *parent, unsigned long asce,
return sg;
/* Create a new shadow gmap */
limit = -1UL >> (33 - (((asce & _ASCE_TYPE_MASK) >> 2) * 11));
+ if (asce & _ASCE_REAL_SPACE)
+ limit = -1UL;
new = gmap_alloc(limit);
if (!new)
return ERR_PTR(-ENOMEM);
@@ -1455,6 +1457,12 @@ struct gmap *gmap_shadow(struct gmap *parent, unsigned long asce,
}
atomic_set(&new->ref_count, 2);
list_add(&new->list, &parent->children);
+ if (asce & _ASCE_REAL_SPACE) {
+ /* nothing to protect, return right away */
+ new->initialized = true;
+ spin_unlock(&parent->shadow_lock);
+ return new;
+ }
spin_unlock(&parent->shadow_lock);
/* protect after insertion, so it will get properly invalidated */
down_read(&parent->mm->mmap_sem);
@@ -1479,6 +1487,7 @@ EXPORT_SYMBOL_GPL(gmap_shadow);
* @sg: pointer to the shadow guest address space structure
* @saddr: faulting address in the shadow gmap
* @r2t: parent gmap address of the region 2 table to get shadowed
+ * @fake: r2t references contiguous guest memory block, not a r2t
*
* The r2t parameter specifies the address of the source table. The
* four pages of the source table are made read-only in the parent gmap
@@ -1491,7 +1500,8 @@ EXPORT_SYMBOL_GPL(gmap_shadow);
*
* Called with sg->mm->mmap_sem in read.
*/
-int gmap_shadow_r2t(struct gmap *sg, unsigned long saddr, unsigned long r2t)
+int gmap_shadow_r2t(struct gmap *sg, unsigned long saddr, unsigned long r2t,
+ int fake)
{
unsigned long raddr, origin, offset, len;
unsigned long *s_r2t, *table;
@@ -1504,6 +1514,8 @@ int gmap_shadow_r2t(struct gmap *sg, unsigned long saddr, unsigned long r2t)
if (!page)
return -ENOMEM;
page->index = r2t & _REGION_ENTRY_ORIGIN;
+ if (fake)
+ page->index |= GMAP_SHADOW_FAKE_TABLE;
s_r2t = (unsigned long *) page_to_phys(page);
/* Install shadow region second table */
spin_lock(&sg->guest_table_lock);
@@ -1526,6 +1538,12 @@ int gmap_shadow_r2t(struct gmap *sg, unsigned long saddr, unsigned long r2t)
if (sg->edat_level >= 1)
*table |= (r2t & _REGION_ENTRY_PROTECT);
list_add(&page->lru, &sg->crst_list);
+ if (fake) {
+ /* nothing to protect for fake tables */
+ *table &= ~_REGION_ENTRY_INVALID;
+ spin_unlock(&sg->guest_table_lock);
+ return 0;
+ }
spin_unlock(&sg->guest_table_lock);
/* Make r2t read-only in parent gmap page table */
raddr = (saddr & 0xffe0000000000000UL) | _SHADOW_RMAP_REGION1;
@@ -1558,6 +1576,7 @@ EXPORT_SYMBOL_GPL(gmap_shadow_r2t);
* @sg: pointer to the shadow guest address space structure
* @saddr: faulting address in the shadow gmap
* @r3t: parent gmap address of the region 3 table to get shadowed
+ * @fake: r3t references contiguous guest memory block, not a r3t
*
* Returns 0 if successfully shadowed or already shadowed, -EAGAIN if the
* shadow table structure is incomplete, -ENOMEM if out of memory and
@@ -1565,7 +1584,8 @@ EXPORT_SYMBOL_GPL(gmap_shadow_r2t);
*
* Called with sg->mm->mmap_sem in read.
*/
-int gmap_shadow_r3t(struct gmap *sg, unsigned long saddr, unsigned long r3t)
+int gmap_shadow_r3t(struct gmap *sg, unsigned long saddr, unsigned long r3t,
+ int fake)
{
unsigned long raddr, origin, offset, len;
unsigned long *s_r3t, *table;
@@ -1578,6 +1598,8 @@ int gmap_shadow_r3t(struct gmap *sg, unsigned long saddr, unsigned long r3t)
if (!page)
return -ENOMEM;
page->index = r3t & _REGION_ENTRY_ORIGIN;
+ if (fake)
+ page->index |= GMAP_SHADOW_FAKE_TABLE;
s_r3t = (unsigned long *) page_to_phys(page);
/* Install shadow region second table */
spin_lock(&sg->guest_table_lock);
@@ -1599,6 +1621,12 @@ int gmap_shadow_r3t(struct gmap *sg, unsigned long saddr, unsigned long r3t)
if (sg->edat_level >= 1)
*table |= (r3t & _REGION_ENTRY_PROTECT);
list_add(&page->lru, &sg->crst_list);
+ if (fake) {
+ /* nothing to protect for fake tables */
+ *table &= ~_REGION_ENTRY_INVALID;
+ spin_unlock(&sg->guest_table_lock);
+ return 0;
+ }
spin_unlock(&sg->guest_table_lock);
/* Make r3t read-only in parent gmap page table */
raddr = (saddr & 0xfffffc0000000000UL) | _SHADOW_RMAP_REGION2;
@@ -1932,7 +1960,8 @@ static void gmap_shadow_notify(struct gmap *sg, unsigned long vmaddr,
/* Check for top level table */
start = sg->orig_asce & _ASCE_ORIGIN;
end = start + ((sg->orig_asce & _ASCE_TABLE_LENGTH) + 1) * 4096;
- if (gaddr >= start && gaddr < end) {
+ if (!(sg->orig_asce & _ASCE_REAL_SPACE) && gaddr >= start &&
+ gaddr < end) {
/* The complete shadow table has to go */
gmap_unshadow(sg);
spin_unlock(&sg->guest_table_lock);
--
2.5.5
^ permalink raw reply related [flat|nested] 53+ messages in thread* [GIT PULL 20/51] s390/mm: limit number of real-space gmap shadows
2016-06-21 13:12 [GIT PULL 00/51] KVM: s390: vSIE (nested virtualization) feature for 4.8 (kvm/next) Christian Borntraeger
` (18 preceding siblings ...)
2016-06-21 13:12 ` [GIT PULL 19/51] s390/mm: support real-space for gmap shadows Christian Borntraeger
@ 2016-06-21 13:12 ` Christian Borntraeger
2016-06-21 13:12 ` [GIT PULL 21/51] s390/mm: remember the int code for the last gmap fault Christian Borntraeger
` (31 subsequent siblings)
51 siblings, 0 replies; 53+ messages in thread
From: Christian Borntraeger @ 2016-06-21 13:12 UTC (permalink / raw)
To: Paolo Bonzini, Radim Krčmář
Cc: KVM, Cornelia Huck, linux-s390, Christian Borntraeger,
David Hildenbrand, Martin Schwidefsky
From: David Hildenbrand <dahi@linux.vnet.ibm.com>
We have no known user of real-space designation and only support it to
be architecture compliant.
Gmap shadows with real-space designation are never unshadowed
automatically, as there is nothing to protect for the top level table.
So let's simply limit the number of such shadows to one by removing
existing ones on creation of another one.
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
arch/s390/mm/gmap.c | 13 +++++++++++++
1 file changed, 13 insertions(+)
diff --git a/arch/s390/mm/gmap.c b/arch/s390/mm/gmap.c
index c07d64f..4a1434b 100644
--- a/arch/s390/mm/gmap.c
+++ b/arch/s390/mm/gmap.c
@@ -1455,6 +1455,19 @@ struct gmap *gmap_shadow(struct gmap *parent, unsigned long asce,
gmap_free(new);
return sg;
}
+ if (asce & _ASCE_REAL_SPACE) {
+ /* only allow one real-space gmap shadow */
+ list_for_each_entry(sg, &parent->children, list) {
+ if (sg->orig_asce & _ASCE_REAL_SPACE) {
+ spin_lock(&sg->guest_table_lock);
+ gmap_unshadow(sg);
+ spin_unlock(&sg->guest_table_lock);
+ list_del(&sg->list);
+ gmap_put(sg);
+ break;
+ }
+ }
+ }
atomic_set(&new->ref_count, 2);
list_add(&new->list, &parent->children);
if (asce & _ASCE_REAL_SPACE) {
--
2.5.5
^ permalink raw reply related [flat|nested] 53+ messages in thread* [GIT PULL 21/51] s390/mm: remember the int code for the last gmap fault
2016-06-21 13:12 [GIT PULL 00/51] KVM: s390: vSIE (nested virtualization) feature for 4.8 (kvm/next) Christian Borntraeger
` (19 preceding siblings ...)
2016-06-21 13:12 ` [GIT PULL 20/51] s390/mm: limit number of real-space " Christian Borntraeger
@ 2016-06-21 13:12 ` Christian Borntraeger
2016-06-21 13:13 ` [GIT PULL 22/51] s390/mm: allow to check if a gmap shadow is valid Christian Borntraeger
` (30 subsequent siblings)
51 siblings, 0 replies; 53+ messages in thread
From: Christian Borntraeger @ 2016-06-21 13:12 UTC (permalink / raw)
To: Paolo Bonzini, Radim Krčmář
Cc: KVM, Cornelia Huck, linux-s390, Christian Borntraeger,
David Hildenbrand, Martin Schwidefsky
From: David Hildenbrand <dahi@linux.vnet.ibm.com>
For nested virtualization, we want to know if we are handling a protection
exception, because these can directly be forwarded to the guest without
additional checks.
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
arch/s390/include/asm/processor.h | 1 +
arch/s390/mm/fault.c | 1 +
2 files changed, 2 insertions(+)
diff --git a/arch/s390/include/asm/processor.h b/arch/s390/include/asm/processor.h
index 94c80b6..8c2922f 100644
--- a/arch/s390/include/asm/processor.h
+++ b/arch/s390/include/asm/processor.h
@@ -110,6 +110,7 @@ struct thread_struct {
mm_segment_t mm_segment;
unsigned long gmap_addr; /* address of last gmap fault. */
unsigned int gmap_write_flag; /* gmap fault write indication */
+ unsigned int gmap_int_code; /* int code of last gmap fault */
unsigned int gmap_pfault; /* signal of a pending guest pfault */
struct per_regs per_user; /* User specified PER registers */
struct per_event per_event; /* Cause of the last PER trap */
diff --git a/arch/s390/mm/fault.c b/arch/s390/mm/fault.c
index b84416c..730e0d3 100644
--- a/arch/s390/mm/fault.c
+++ b/arch/s390/mm/fault.c
@@ -419,6 +419,7 @@ static inline int do_exception(struct pt_regs *regs, int access)
if (gmap) {
current->thread.gmap_addr = address;
current->thread.gmap_write_flag = !!(flags & FAULT_FLAG_WRITE);
+ current->thread.gmap_int_code = regs->int_code & 0xffff;
address = __gmap_translate(gmap, address);
if (address == -EFAULT) {
fault = VM_FAULT_BADMAP;
--
2.5.5
^ permalink raw reply related [flat|nested] 53+ messages in thread* [GIT PULL 22/51] s390/mm: allow to check if a gmap shadow is valid
2016-06-21 13:12 [GIT PULL 00/51] KVM: s390: vSIE (nested virtualization) feature for 4.8 (kvm/next) Christian Borntraeger
` (20 preceding siblings ...)
2016-06-21 13:12 ` [GIT PULL 21/51] s390/mm: remember the int code for the last gmap fault Christian Borntraeger
@ 2016-06-21 13:13 ` Christian Borntraeger
2016-06-21 13:13 ` [GIT PULL 23/51] s390/mm: don't fault everything in read-write in gmap_pte_op_fixup() Christian Borntraeger
` (29 subsequent siblings)
51 siblings, 0 replies; 53+ messages in thread
From: Christian Borntraeger @ 2016-06-21 13:13 UTC (permalink / raw)
To: Paolo Bonzini, Radim Krčmář
Cc: KVM, Cornelia Huck, linux-s390, Christian Borntraeger,
David Hildenbrand, Martin Schwidefsky
From: David Hildenbrand <dahi@linux.vnet.ibm.com>
It will be very helpful to have a mechanism to check without any locks
if a given gmap shadow is still valid and matches the given properties.
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
arch/s390/include/asm/gmap.h | 1 +
arch/s390/mm/gmap.c | 20 ++++++++++++++++++++
2 files changed, 21 insertions(+)
diff --git a/arch/s390/include/asm/gmap.h b/arch/s390/include/asm/gmap.h
index 752cf47..c67fb85 100644
--- a/arch/s390/include/asm/gmap.h
+++ b/arch/s390/include/asm/gmap.h
@@ -109,6 +109,7 @@ int gmap_read_table(struct gmap *gmap, unsigned long gaddr, unsigned long *val);
struct gmap *gmap_shadow(struct gmap *parent, unsigned long asce,
int edat_level);
+int gmap_shadow_valid(struct gmap *sg, unsigned long asce, int edat_level);
int gmap_shadow_r2t(struct gmap *sg, unsigned long saddr, unsigned long r2t,
int fake);
int gmap_shadow_r3t(struct gmap *sg, unsigned long saddr, unsigned long r3t,
diff --git a/arch/s390/mm/gmap.c b/arch/s390/mm/gmap.c
index 4a1434b..d00e4ab 100644
--- a/arch/s390/mm/gmap.c
+++ b/arch/s390/mm/gmap.c
@@ -1408,6 +1408,26 @@ static struct gmap *gmap_find_shadow(struct gmap *parent, unsigned long asce,
}
/**
+ * gmap_shadow_valid - check if a shadow guest address space matches the
+ * given properties and is still valid
+ * @sg: pointer to the shadow guest address space structure
+ * @asce: ASCE for which the shadow table is requested
+ * @edat_level: edat level to be used for the shadow translation
+ *
+ * Returns 1 if the gmap shadow is still valid and matches the given
+ * properties, the caller can continue using it. Returns 0 otherwise, the
+ * caller has to request a new shadow gmap in this case.
+ *
+ */
+int gmap_shadow_valid(struct gmap *sg, unsigned long asce, int edat_level)
+{
+ if (sg->removed)
+ return 0;
+ return sg->orig_asce == asce && sg->edat_level == edat_level;
+}
+EXPORT_SYMBOL_GPL(gmap_shadow_valid);
+
+/**
* gmap_shadow - create/find a shadow guest address space
* @parent: pointer to the parent gmap
* @asce: ASCE for which the shadow table is created
--
2.5.5
^ permalink raw reply related [flat|nested] 53+ messages in thread* [GIT PULL 23/51] s390/mm: don't fault everything in read-write in gmap_pte_op_fixup()
2016-06-21 13:12 [GIT PULL 00/51] KVM: s390: vSIE (nested virtualization) feature for 4.8 (kvm/next) Christian Borntraeger
` (21 preceding siblings ...)
2016-06-21 13:13 ` [GIT PULL 22/51] s390/mm: allow to check if a gmap shadow is valid Christian Borntraeger
@ 2016-06-21 13:13 ` Christian Borntraeger
2016-06-21 13:13 ` [GIT PULL 24/51] KVM: s390: fast path for shadow gmaps in gmap notifier Christian Borntraeger
` (28 subsequent siblings)
51 siblings, 0 replies; 53+ messages in thread
From: Christian Borntraeger @ 2016-06-21 13:13 UTC (permalink / raw)
To: Paolo Bonzini, Radim Krčmář
Cc: KVM, Cornelia Huck, linux-s390, Christian Borntraeger,
David Hildenbrand, Martin Schwidefsky
From: David Hildenbrand <dahi@linux.vnet.ibm.com>
Let's not fault in everything in read-write but limit it to read-only
where possible.
When restricting access rights, we already have the required protection
level in our hands. When reading from guest 2 storage (gmap_read_table),
it is obviously PROT_READ. When shadowing a pte, the required protection
level is given via the guest 2 provided pte.
Based on an initial patch by Martin Schwidefsky.
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
arch/s390/mm/gmap.c | 17 +++++++++++------
1 file changed, 11 insertions(+), 6 deletions(-)
diff --git a/arch/s390/mm/gmap.c b/arch/s390/mm/gmap.c
index d00e4ab..738d754 100644
--- a/arch/s390/mm/gmap.c
+++ b/arch/s390/mm/gmap.c
@@ -811,19 +811,22 @@ static pte_t *gmap_pte_op_walk(struct gmap *gmap, unsigned long gaddr,
* @gmap: pointer to guest mapping meta data structure
* @gaddr: virtual address in the guest address space
* @vmaddr: address in the host process address space
+ * @prot: indicates access rights: PROT_NONE, PROT_READ or PROT_WRITE
*
* Returns 0 if the caller can retry __gmap_translate (might fail again),
* -ENOMEM if out of memory and -EFAULT if anything goes wrong while fixing
* up or connecting the gmap page table.
*/
static int gmap_pte_op_fixup(struct gmap *gmap, unsigned long gaddr,
- unsigned long vmaddr)
+ unsigned long vmaddr, int prot)
{
struct mm_struct *mm = gmap->mm;
+ unsigned int fault_flags;
bool unlocked = false;
BUG_ON(gmap_is_shadow(gmap));
- if (fixup_user_fault(current, mm, vmaddr, FAULT_FLAG_WRITE, &unlocked))
+ fault_flags = (prot == PROT_WRITE) ? FAULT_FLAG_WRITE : 0;
+ if (fixup_user_fault(current, mm, vmaddr, fault_flags, &unlocked))
return -EFAULT;
if (unlocked)
/* lost mmap_sem, caller has to retry __gmap_translate */
@@ -875,7 +878,7 @@ static int gmap_protect_range(struct gmap *gmap, unsigned long gaddr,
vmaddr = __gmap_translate(gmap, gaddr);
if (IS_ERR_VALUE(vmaddr))
return vmaddr;
- rc = gmap_pte_op_fixup(gmap, gaddr, vmaddr);
+ rc = gmap_pte_op_fixup(gmap, gaddr, vmaddr, prot);
if (rc)
return rc;
continue;
@@ -957,7 +960,7 @@ int gmap_read_table(struct gmap *gmap, unsigned long gaddr, unsigned long *val)
rc = vmaddr;
break;
}
- rc = gmap_pte_op_fixup(gmap, gaddr, vmaddr);
+ rc = gmap_pte_op_fixup(gmap, gaddr, vmaddr, PROT_READ);
if (rc)
break;
}
@@ -1041,7 +1044,7 @@ static int gmap_protect_rmap(struct gmap *sg, unsigned long raddr,
radix_tree_preload_end();
if (rc) {
kfree(rmap);
- rc = gmap_pte_op_fixup(parent, paddr, vmaddr);
+ rc = gmap_pte_op_fixup(parent, paddr, vmaddr, prot);
if (rc)
return rc;
continue;
@@ -1910,10 +1913,12 @@ int gmap_shadow_page(struct gmap *sg, unsigned long saddr, pte_t pte)
unsigned long vmaddr, paddr;
spinlock_t *ptl;
pte_t *sptep, *tptep;
+ int prot;
int rc;
BUG_ON(!gmap_is_shadow(sg));
parent = sg->parent;
+ prot = (pte_val(pte) & _PAGE_PROTECT) ? PROT_READ : PROT_WRITE;
rmap = kzalloc(sizeof(*rmap), GFP_KERNEL);
if (!rmap)
@@ -1955,7 +1960,7 @@ int gmap_shadow_page(struct gmap *sg, unsigned long saddr, pte_t pte)
radix_tree_preload_end();
if (!rc)
break;
- rc = gmap_pte_op_fixup(parent, paddr, vmaddr);
+ rc = gmap_pte_op_fixup(parent, paddr, vmaddr, prot);
if (rc)
break;
}
--
2.5.5
^ permalink raw reply related [flat|nested] 53+ messages in thread* [GIT PULL 24/51] KVM: s390: fast path for shadow gmaps in gmap notifier
2016-06-21 13:12 [GIT PULL 00/51] KVM: s390: vSIE (nested virtualization) feature for 4.8 (kvm/next) Christian Borntraeger
` (22 preceding siblings ...)
2016-06-21 13:13 ` [GIT PULL 23/51] s390/mm: don't fault everything in read-write in gmap_pte_op_fixup() Christian Borntraeger
@ 2016-06-21 13:13 ` Christian Borntraeger
2016-06-21 13:13 ` [GIT PULL 25/51] KVM: s390: backup the currently enabled gmap when scheduled out Christian Borntraeger
` (27 subsequent siblings)
51 siblings, 0 replies; 53+ messages in thread
From: Christian Borntraeger @ 2016-06-21 13:13 UTC (permalink / raw)
To: Paolo Bonzini, Radim Krčmář
Cc: KVM, Cornelia Huck, linux-s390, Christian Borntraeger,
David Hildenbrand, Martin Schwidefsky
From: David Hildenbrand <dahi@linux.vnet.ibm.com>
The default kvm gmap notifier doesn't have to handle shadow gmaps.
So let's just directly exit in case we get notified about one.
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
arch/s390/kvm/kvm-s390.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 9dd5298..45a8316 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -1986,6 +1986,8 @@ static void kvm_gmap_notifier(struct gmap *gmap, unsigned long start,
unsigned long prefix;
int i;
+ if (gmap_is_shadow(gmap))
+ return;
if (start >= 1UL << 31)
/* We are only interested in prefix pages */
return;
--
2.5.5
^ permalink raw reply related [flat|nested] 53+ messages in thread* [GIT PULL 25/51] KVM: s390: backup the currently enabled gmap when scheduled out
2016-06-21 13:12 [GIT PULL 00/51] KVM: s390: vSIE (nested virtualization) feature for 4.8 (kvm/next) Christian Borntraeger
` (23 preceding siblings ...)
2016-06-21 13:13 ` [GIT PULL 24/51] KVM: s390: fast path for shadow gmaps in gmap notifier Christian Borntraeger
@ 2016-06-21 13:13 ` Christian Borntraeger
2016-06-21 13:13 ` [GIT PULL 26/51] s390: introduce page_to_virt() and pfn_to_virt() Christian Borntraeger
` (26 subsequent siblings)
51 siblings, 0 replies; 53+ messages in thread
From: Christian Borntraeger @ 2016-06-21 13:13 UTC (permalink / raw)
To: Paolo Bonzini, Radim Krčmář
Cc: KVM, Cornelia Huck, linux-s390, Christian Borntraeger,
David Hildenbrand, Martin Schwidefsky
From: David Hildenbrand <dahi@linux.vnet.ibm.com>
Nested virtualization will have to enable own gmaps. Current code
would enable the wrong gmap whenever scheduled out and back in,
therefore resulting in the wrong gmap being enabled.
This patch reenables the last enabled gmap, therefore avoiding having to
touch vcpu->arch.gmap when enabling a different gmap.
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
arch/s390/include/asm/gmap.h | 1 +
arch/s390/include/asm/kvm_host.h | 2 ++
arch/s390/kvm/kvm-s390.c | 8 +++++---
arch/s390/mm/gmap.c | 11 +++++++++++
4 files changed, 19 insertions(+), 3 deletions(-)
diff --git a/arch/s390/include/asm/gmap.h b/arch/s390/include/asm/gmap.h
index c67fb85..741ddba 100644
--- a/arch/s390/include/asm/gmap.h
+++ b/arch/s390/include/asm/gmap.h
@@ -94,6 +94,7 @@ void gmap_put(struct gmap *gmap);
void gmap_enable(struct gmap *gmap);
void gmap_disable(struct gmap *gmap);
+struct gmap *gmap_get_enabled(void);
int gmap_map_segment(struct gmap *gmap, unsigned long from,
unsigned long to, unsigned long len);
int gmap_unmap_segment(struct gmap *gmap, unsigned long to, unsigned long len);
diff --git a/arch/s390/include/asm/kvm_host.h b/arch/s390/include/asm/kvm_host.h
index 9eed5c1..96bef30 100644
--- a/arch/s390/include/asm/kvm_host.h
+++ b/arch/s390/include/asm/kvm_host.h
@@ -551,6 +551,8 @@ struct kvm_vcpu_arch {
struct hrtimer ckc_timer;
struct kvm_s390_pgm_info pgm;
struct gmap *gmap;
+ /* backup location for the currently enabled gmap when scheduled out */
+ struct gmap *enabled_gmap;
struct kvm_guestdbg_info_arch guestdbg;
unsigned long pfault_token;
unsigned long pfault_select;
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 45a8316..a890f7d 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -1719,7 +1719,7 @@ void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
save_access_regs(vcpu->arch.host_acrs);
restore_access_regs(vcpu->run->s.regs.acrs);
- gmap_enable(vcpu->arch.gmap);
+ gmap_enable(vcpu->arch.enabled_gmap);
atomic_or(CPUSTAT_RUNNING, &vcpu->arch.sie_block->cpuflags);
if (vcpu->arch.cputm_enabled && !is_vcpu_idle(vcpu))
__start_cpu_timer_accounting(vcpu);
@@ -1732,7 +1732,8 @@ void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
if (vcpu->arch.cputm_enabled && !is_vcpu_idle(vcpu))
__stop_cpu_timer_accounting(vcpu);
atomic_andnot(CPUSTAT_RUNNING, &vcpu->arch.sie_block->cpuflags);
- gmap_disable(vcpu->arch.gmap);
+ vcpu->arch.enabled_gmap = gmap_get_enabled();
+ gmap_disable(vcpu->arch.enabled_gmap);
/* Save guest register state */
save_fpu_regs();
@@ -1781,7 +1782,8 @@ void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
vcpu->arch.gmap = vcpu->kvm->arch.gmap;
sca_add_vcpu(vcpu);
}
-
+ /* make vcpu_load load the right gmap on the first trigger */
+ vcpu->arch.enabled_gmap = vcpu->arch.gmap;
}
static void kvm_s390_vcpu_crypto_setup(struct kvm_vcpu *vcpu)
diff --git a/arch/s390/mm/gmap.c b/arch/s390/mm/gmap.c
index 738d754..af0ae6d 100644
--- a/arch/s390/mm/gmap.c
+++ b/arch/s390/mm/gmap.c
@@ -270,6 +270,17 @@ void gmap_disable(struct gmap *gmap)
}
EXPORT_SYMBOL_GPL(gmap_disable);
+/**
+ * gmap_get_enabled - get a pointer to the currently enabled gmap
+ *
+ * Returns a pointer to the currently enabled gmap. 0 if none is enabled.
+ */
+struct gmap *gmap_get_enabled(void)
+{
+ return (struct gmap *) S390_lowcore.gmap;
+}
+EXPORT_SYMBOL_GPL(gmap_get_enabled);
+
/*
* gmap_alloc_table is assumed to be called with mmap_sem held
*/
--
2.5.5
^ permalink raw reply related [flat|nested] 53+ messages in thread* [GIT PULL 26/51] s390: introduce page_to_virt() and pfn_to_virt()
2016-06-21 13:12 [GIT PULL 00/51] KVM: s390: vSIE (nested virtualization) feature for 4.8 (kvm/next) Christian Borntraeger
` (24 preceding siblings ...)
2016-06-21 13:13 ` [GIT PULL 25/51] KVM: s390: backup the currently enabled gmap when scheduled out Christian Borntraeger
@ 2016-06-21 13:13 ` Christian Borntraeger
2016-06-21 13:13 ` [GIT PULL 27/51] mm/page_ref: introduce page_ref_inc_return Christian Borntraeger
` (25 subsequent siblings)
51 siblings, 0 replies; 53+ messages in thread
From: Christian Borntraeger @ 2016-06-21 13:13 UTC (permalink / raw)
To: Paolo Bonzini, Radim Krčmář
Cc: KVM, Cornelia Huck, linux-s390, Christian Borntraeger,
David Hildenbrand, Martin Schwidefsky
From: David Hildenbrand <dahi@linux.vnet.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
arch/s390/include/asm/page.h | 2 ++
1 file changed, 2 insertions(+)
diff --git a/arch/s390/include/asm/page.h b/arch/s390/include/asm/page.h
index f874e7d5..b5edff3 100644
--- a/arch/s390/include/asm/page.h
+++ b/arch/s390/include/asm/page.h
@@ -147,6 +147,8 @@ static inline int devmem_is_allowed(unsigned long pfn)
#define virt_to_page(kaddr) pfn_to_page(__pa(kaddr) >> PAGE_SHIFT)
#define page_to_phys(page) (page_to_pfn(page) << PAGE_SHIFT)
#define virt_addr_valid(kaddr) pfn_valid(__pa(kaddr) >> PAGE_SHIFT)
+#define pfn_to_virt(pfn) __va((pfn) << PAGE_SHIFT)
+#define page_to_virt(page) pfn_to_virt(page_to_pfn(page))
#define VM_DATA_DEFAULT_FLAGS (VM_READ | VM_WRITE | \
VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC)
--
2.5.5
^ permalink raw reply related [flat|nested] 53+ messages in thread* [GIT PULL 27/51] mm/page_ref: introduce page_ref_inc_return
2016-06-21 13:12 [GIT PULL 00/51] KVM: s390: vSIE (nested virtualization) feature for 4.8 (kvm/next) Christian Borntraeger
` (25 preceding siblings ...)
2016-06-21 13:13 ` [GIT PULL 26/51] s390: introduce page_to_virt() and pfn_to_virt() Christian Borntraeger
@ 2016-06-21 13:13 ` Christian Borntraeger
2016-06-21 13:13 ` [GIT PULL 28/51] KVM: s390: vsie: initial support for nested virtualization Christian Borntraeger
` (24 subsequent siblings)
51 siblings, 0 replies; 53+ messages in thread
From: Christian Borntraeger @ 2016-06-21 13:13 UTC (permalink / raw)
To: Paolo Bonzini, Radim Krčmář
Cc: KVM, Cornelia Huck, linux-s390, Christian Borntraeger,
David Hildenbrand, Martin Schwidefsky
From: David Hildenbrand <dahi@linux.vnet.ibm.com>
Let's introduce that helper.
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
include/linux/page_ref.h | 9 +++++++++
1 file changed, 9 insertions(+)
diff --git a/include/linux/page_ref.h b/include/linux/page_ref.h
index 8b5e0a9..610e132 100644
--- a/include/linux/page_ref.h
+++ b/include/linux/page_ref.h
@@ -124,6 +124,15 @@ static inline int page_ref_sub_and_test(struct page *page, int nr)
return ret;
}
+static inline int page_ref_inc_return(struct page *page)
+{
+ int ret = atomic_inc_return(&page->_refcount);
+
+ if (page_ref_tracepoint_active(__tracepoint_page_ref_mod_and_return))
+ __page_ref_mod_and_return(page, 1, ret);
+ return ret;
+}
+
static inline int page_ref_dec_and_test(struct page *page)
{
int ret = atomic_dec_and_test(&page->_refcount);
--
2.5.5
^ permalink raw reply related [flat|nested] 53+ messages in thread* [GIT PULL 28/51] KVM: s390: vsie: initial support for nested virtualization
2016-06-21 13:12 [GIT PULL 00/51] KVM: s390: vSIE (nested virtualization) feature for 4.8 (kvm/next) Christian Borntraeger
` (26 preceding siblings ...)
2016-06-21 13:13 ` [GIT PULL 27/51] mm/page_ref: introduce page_ref_inc_return Christian Borntraeger
@ 2016-06-21 13:13 ` Christian Borntraeger
2016-06-21 13:13 ` [GIT PULL 29/51] KVM: s390: vsie: optimize gmap prefix mapping Christian Borntraeger
` (23 subsequent siblings)
51 siblings, 0 replies; 53+ messages in thread
From: Christian Borntraeger @ 2016-06-21 13:13 UTC (permalink / raw)
To: Paolo Bonzini, Radim Krčmář
Cc: KVM, Cornelia Huck, linux-s390, Christian Borntraeger,
David Hildenbrand, Martin Schwidefsky
From: David Hildenbrand <dahi@linux.vnet.ibm.com>
This patch adds basic support for nested virtualization on s390x, called
VSIE (virtual SIE) and allows it to be used by the guest if the necessary
facilities are supported by the hardware and enabled for the guest.
In order to make this work, we have to shadow the sie control block
provided by guest 2. In order to gain some performance, we have to
reuse the same shadow blocks as good as possible. For now, we allow
as many shadow blocks as we have VCPUs (that way, every VCPU can run the
VSIE concurrently).
We have to watch out for the prefix getting unmapped out of our shadow
gmap and properly get the VCPU out of VSIE in that case, to fault the
prefix pages back in. We use the PROG_REQUEST bit for that purpose.
This patch is based on an initial prototype by Tobias Elpelt.
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
arch/s390/include/asm/kvm_host.h | 15 +-
arch/s390/include/uapi/asm/kvm.h | 1 +
arch/s390/kvm/Makefile | 2 +-
arch/s390/kvm/kvm-s390.c | 15 +
arch/s390/kvm/kvm-s390.h | 7 +
arch/s390/kvm/priv.c | 1 +
arch/s390/kvm/vsie.c | 755 +++++++++++++++++++++++++++++++++++++++
7 files changed, 794 insertions(+), 2 deletions(-)
create mode 100644 arch/s390/kvm/vsie.c
diff --git a/arch/s390/include/asm/kvm_host.h b/arch/s390/include/asm/kvm_host.h
index 96bef30..255609c 100644
--- a/arch/s390/include/asm/kvm_host.h
+++ b/arch/s390/include/asm/kvm_host.h
@@ -145,7 +145,7 @@ struct kvm_s390_sie_block {
__u64 cputm; /* 0x0028 */
__u64 ckc; /* 0x0030 */
__u64 epoch; /* 0x0038 */
- __u8 reserved40[4]; /* 0x0040 */
+ __u32 svcc; /* 0x0040 */
#define LCTL_CR0 0x8000
#define LCTL_CR6 0x0200
#define LCTL_CR9 0x0040
@@ -167,6 +167,9 @@ struct kvm_s390_sie_block {
#define ICPT_INST 0x04
#define ICPT_PROGI 0x08
#define ICPT_INSTPROGI 0x0C
+#define ICPT_EXTINT 0x14
+#define ICPT_VALIDITY 0x20
+#define ICPT_STOP 0x28
#define ICPT_OPEREXC 0x2C
#define ICPT_PARTEXEC 0x38
#define ICPT_IOINST 0x40
@@ -281,6 +284,7 @@ struct kvm_vcpu_stat {
u32 instruction_stsi;
u32 instruction_stfl;
u32 instruction_tprot;
+ u32 instruction_sie;
u32 instruction_essa;
u32 instruction_sthyi;
u32 instruction_sigp_sense;
@@ -637,6 +641,14 @@ struct sie_page2 {
u8 reserved900[0x1000 - 0x900]; /* 0x0900 */
} __packed;
+struct kvm_s390_vsie {
+ struct mutex mutex;
+ struct radix_tree_root addr_to_page;
+ int page_count;
+ int next;
+ struct page *pages[KVM_MAX_VCPUS];
+};
+
struct kvm_arch{
void *sca;
int use_esca;
@@ -661,6 +673,7 @@ struct kvm_arch{
struct sie_page2 *sie_page2;
struct kvm_s390_cpu_model model;
struct kvm_s390_crypto crypto;
+ struct kvm_s390_vsie vsie;
u64 epoch;
/* subset of available cpu features enabled by user space */
DECLARE_BITMAP(cpu_feat, KVM_S390_VM_CPU_FEAT_NR_BITS);
diff --git a/arch/s390/include/uapi/asm/kvm.h b/arch/s390/include/uapi/asm/kvm.h
index f0818d7..62423b1 100644
--- a/arch/s390/include/uapi/asm/kvm.h
+++ b/arch/s390/include/uapi/asm/kvm.h
@@ -98,6 +98,7 @@ struct kvm_s390_vm_cpu_machine {
#define KVM_S390_VM_CPU_FEAT_NR_BITS 1024
#define KVM_S390_VM_CPU_FEAT_ESOP 0
+#define KVM_S390_VM_CPU_FEAT_SIEF2 1
struct kvm_s390_vm_cpu_feat {
__u64 feat[16];
};
diff --git a/arch/s390/kvm/Makefile b/arch/s390/kvm/Makefile
index 82e73e2..09a9e6d 100644
--- a/arch/s390/kvm/Makefile
+++ b/arch/s390/kvm/Makefile
@@ -12,6 +12,6 @@ common-objs = $(KVM)/kvm_main.o $(KVM)/eventfd.o $(KVM)/async_pf.o $(KVM)/irqch
ccflags-y := -Ivirt/kvm -Iarch/s390/kvm
kvm-objs := $(common-objs) kvm-s390.o intercept.o interrupt.o priv.o sigp.o
-kvm-objs += diag.o gaccess.o guestdbg.o sthyi.o
+kvm-objs += diag.o gaccess.o guestdbg.o sthyi.o vsie.o
obj-$(CONFIG_KVM) += kvm.o
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index a890f7d..3fb1242 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -99,6 +99,7 @@ struct kvm_stats_debugfs_item debugfs_entries[] = {
{ "instruction_stfl", VCPU_STAT(instruction_stfl) },
{ "instruction_tprot", VCPU_STAT(instruction_tprot) },
{ "instruction_sthyi", VCPU_STAT(instruction_sthyi) },
+ { "instruction_sie", VCPU_STAT(instruction_sie) },
{ "instruction_sigp_sense", VCPU_STAT(instruction_sigp_sense) },
{ "instruction_sigp_sense_running", VCPU_STAT(instruction_sigp_sense_running) },
{ "instruction_sigp_external_call", VCPU_STAT(instruction_sigp_external_call) },
@@ -142,6 +143,7 @@ static DECLARE_BITMAP(kvm_s390_available_cpu_feat, KVM_S390_VM_CPU_FEAT_NR_BITS)
static struct kvm_s390_vm_cpu_subfunc kvm_s390_available_subfunc;
static struct gmap_notifier gmap_notifier;
+static struct gmap_notifier vsie_gmap_notifier;
debug_info_t *kvm_s390_dbf;
/* Section: not file related */
@@ -187,6 +189,8 @@ int kvm_arch_hardware_setup(void)
{
gmap_notifier.notifier_call = kvm_gmap_notifier;
gmap_register_pte_notifier(&gmap_notifier);
+ vsie_gmap_notifier.notifier_call = kvm_s390_vsie_gmap_notifier;
+ gmap_register_pte_notifier(&vsie_gmap_notifier);
atomic_notifier_chain_register(&s390_epoch_delta_notifier,
&kvm_clock_notifier);
return 0;
@@ -195,6 +199,7 @@ int kvm_arch_hardware_setup(void)
void kvm_arch_hardware_unsetup(void)
{
gmap_unregister_pte_notifier(&gmap_notifier);
+ gmap_unregister_pte_notifier(&vsie_gmap_notifier);
atomic_notifier_chain_unregister(&s390_epoch_delta_notifier,
&kvm_clock_notifier);
}
@@ -252,6 +257,14 @@ static void kvm_s390_cpu_feat_init(void)
if (MACHINE_HAS_ESOP)
allow_cpu_feat(KVM_S390_VM_CPU_FEAT_ESOP);
+ /*
+ * We need SIE support, ESOP (PROT_READ protection for gmap_shadow),
+ * 64bit SCAO (SCA passthrough) and IDTE (for gmap_shadow unshadowing).
+ */
+ if (!sclp.has_sief2 || !MACHINE_HAS_ESOP || !sclp.has_64bscao ||
+ !test_facility(3))
+ return;
+ allow_cpu_feat(KVM_S390_VM_CPU_FEAT_SIEF2);
}
int kvm_arch_init(void *opaque)
@@ -1406,6 +1419,7 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
kvm->arch.epoch = 0;
spin_lock_init(&kvm->arch.start_stop_lock);
+ kvm_s390_vsie_init(kvm);
KVM_EVENT(3, "vm 0x%pK created by pid %u", kvm, current->pid);
return 0;
@@ -1463,6 +1477,7 @@ void kvm_arch_destroy_vm(struct kvm *kvm)
gmap_remove(kvm->arch.gmap);
kvm_s390_destroy_adapters(kvm);
kvm_s390_clear_float_irqs(kvm);
+ kvm_s390_vsie_destroy(kvm);
KVM_EVENT(3, "vm 0x%pK destroyed", kvm);
}
diff --git a/arch/s390/kvm/kvm-s390.h b/arch/s390/kvm/kvm-s390.h
index 52aa47e..b137fba 100644
--- a/arch/s390/kvm/kvm-s390.h
+++ b/arch/s390/kvm/kvm-s390.h
@@ -252,6 +252,13 @@ int kvm_s390_handle_stctl(struct kvm_vcpu *vcpu);
int kvm_s390_handle_lctl(struct kvm_vcpu *vcpu);
int kvm_s390_handle_eb(struct kvm_vcpu *vcpu);
+/* implemented in vsie.c */
+int kvm_s390_handle_vsie(struct kvm_vcpu *vcpu);
+void kvm_s390_vsie_gmap_notifier(struct gmap *gmap, unsigned long start,
+ unsigned long end);
+void kvm_s390_vsie_init(struct kvm *kvm);
+void kvm_s390_vsie_destroy(struct kvm *kvm);
+
/* implemented in sigp.c */
int kvm_s390_handle_sigp(struct kvm_vcpu *vcpu);
int kvm_s390_handle_sigp_pei(struct kvm_vcpu *vcpu);
diff --git a/arch/s390/kvm/priv.c b/arch/s390/kvm/priv.c
index 3db3be1..c77ad2d 100644
--- a/arch/s390/kvm/priv.c
+++ b/arch/s390/kvm/priv.c
@@ -719,6 +719,7 @@ static const intercept_handler_t b2_handlers[256] = {
[0x10] = handle_set_prefix,
[0x11] = handle_store_prefix,
[0x12] = handle_store_cpu_address,
+ [0x14] = kvm_s390_handle_vsie,
[0x21] = handle_ipte_interlock,
[0x29] = handle_iske,
[0x2a] = handle_rrbe,
diff --git a/arch/s390/kvm/vsie.c b/arch/s390/kvm/vsie.c
new file mode 100644
index 0000000..747d4f9
--- /dev/null
+++ b/arch/s390/kvm/vsie.c
@@ -0,0 +1,755 @@
+/*
+ * kvm nested virtualization support for s390x
+ *
+ * Copyright IBM Corp. 2016
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License (version 2 only)
+ * as published by the Free Software Foundation.
+ *
+ * Author(s): David Hildenbrand <dahi@linux.vnet.ibm.com>
+ */
+#include <linux/vmalloc.h>
+#include <linux/kvm_host.h>
+#include <linux/bug.h>
+#include <linux/list.h>
+#include <linux/bitmap.h>
+#include <asm/gmap.h>
+#include <asm/mmu_context.h>
+#include <asm/sclp.h>
+#include <asm/nmi.h>
+#include "kvm-s390.h"
+#include "gaccess.h"
+
+struct vsie_page {
+ struct kvm_s390_sie_block scb_s; /* 0x0000 */
+ /* the pinned originial scb */
+ struct kvm_s390_sie_block *scb_o; /* 0x0200 */
+ /* the shadow gmap in use by the vsie_page */
+ struct gmap *gmap; /* 0x0208 */
+ __u8 reserved[0x1000 - 0x0210]; /* 0x0210 */
+} __packed;
+
+/* trigger a validity icpt for the given scb */
+static int set_validity_icpt(struct kvm_s390_sie_block *scb,
+ __u16 reason_code)
+{
+ scb->ipa = 0x1000;
+ scb->ipb = ((__u32) reason_code) << 16;
+ scb->icptcode = ICPT_VALIDITY;
+ return 1;
+}
+
+/* mark the prefix as unmapped, this will block the VSIE */
+static void prefix_unmapped(struct vsie_page *vsie_page)
+{
+ atomic_or(PROG_REQUEST, &vsie_page->scb_s.prog20);
+}
+
+/* mark the prefix as unmapped and wait until the VSIE has been left */
+static void prefix_unmapped_sync(struct vsie_page *vsie_page)
+{
+ prefix_unmapped(vsie_page);
+ if (vsie_page->scb_s.prog0c & PROG_IN_SIE)
+ atomic_or(CPUSTAT_STOP_INT, &vsie_page->scb_s.cpuflags);
+ while (vsie_page->scb_s.prog0c & PROG_IN_SIE)
+ cpu_relax();
+}
+
+/* mark the prefix as mapped, this will allow the VSIE to run */
+static void prefix_mapped(struct vsie_page *vsie_page)
+{
+ atomic_andnot(PROG_REQUEST, &vsie_page->scb_s.prog20);
+}
+
+
+/* copy the updated intervention request bits into the shadow scb */
+static void update_intervention_requests(struct vsie_page *vsie_page)
+{
+ const int bits = CPUSTAT_STOP_INT | CPUSTAT_IO_INT | CPUSTAT_EXT_INT;
+ int cpuflags;
+
+ cpuflags = atomic_read(&vsie_page->scb_o->cpuflags);
+ atomic_andnot(bits, &vsie_page->scb_s.cpuflags);
+ atomic_or(cpuflags & bits, &vsie_page->scb_s.cpuflags);
+}
+
+/* shadow (filter and validate) the cpuflags */
+static int prepare_cpuflags(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
+{
+ struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s;
+ struct kvm_s390_sie_block *scb_o = vsie_page->scb_o;
+ int newflags, cpuflags = atomic_read(&scb_o->cpuflags);
+
+ /* we don't allow ESA/390 guests */
+ if (!(cpuflags & CPUSTAT_ZARCH))
+ return set_validity_icpt(scb_s, 0x0001U);
+
+ if (cpuflags & (CPUSTAT_RRF | CPUSTAT_MCDS))
+ return set_validity_icpt(scb_s, 0x0001U);
+ else if (cpuflags & (CPUSTAT_SLSV | CPUSTAT_SLSR))
+ return set_validity_icpt(scb_s, 0x0007U);
+
+ /* intervention requests will be set later */
+ newflags = CPUSTAT_ZARCH;
+
+ atomic_set(&scb_s->cpuflags, newflags);
+ return 0;
+}
+
+/* unshadow the scb, copying parameters back to the real scb */
+static void unshadow_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
+{
+ struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s;
+ struct kvm_s390_sie_block *scb_o = vsie_page->scb_o;
+
+ /* interception */
+ scb_o->icptcode = scb_s->icptcode;
+ scb_o->icptstatus = scb_s->icptstatus;
+ scb_o->ipa = scb_s->ipa;
+ scb_o->ipb = scb_s->ipb;
+ scb_o->gbea = scb_s->gbea;
+
+ /* timer */
+ scb_o->cputm = scb_s->cputm;
+ scb_o->ckc = scb_s->ckc;
+ scb_o->todpr = scb_s->todpr;
+
+ /* guest state */
+ scb_o->gpsw = scb_s->gpsw;
+ scb_o->gg14 = scb_s->gg14;
+ scb_o->gg15 = scb_s->gg15;
+ memcpy(scb_o->gcr, scb_s->gcr, 128);
+ scb_o->pp = scb_s->pp;
+
+ /* interrupt intercept */
+ switch (scb_s->icptcode) {
+ case ICPT_PROGI:
+ case ICPT_INSTPROGI:
+ case ICPT_EXTINT:
+ memcpy((void *)((u64)scb_o + 0xc0),
+ (void *)((u64)scb_s + 0xc0), 0xf0 - 0xc0);
+ break;
+ case ICPT_PARTEXEC:
+ /* MVPG only */
+ memcpy((void *)((u64)scb_o + 0xc0),
+ (void *)((u64)scb_s + 0xc0), 0xd0 - 0xc0);
+ break;
+ }
+
+ if (scb_s->ihcpu != 0xffffU)
+ scb_o->ihcpu = scb_s->ihcpu;
+}
+
+/*
+ * Setup the shadow scb by copying and checking the relevant parts of the g2
+ * provided scb.
+ *
+ * Returns: - 0 if the scb has been shadowed
+ * - > 0 if control has to be given to guest 2
+ */
+static int shadow_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
+{
+ struct kvm_s390_sie_block *scb_o = vsie_page->scb_o;
+ struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s;
+ int rc;
+
+ /* make sure we don't have any leftovers when reusing the scb */
+ scb_s->icptcode = 0;
+ scb_s->eca = 0;
+ scb_s->ecb = 0;
+ scb_s->ecb2 = 0;
+ scb_s->ecb3 = 0;
+ scb_s->ecd = 0;
+
+ rc = prepare_cpuflags(vcpu, vsie_page);
+ if (rc)
+ goto out;
+
+ /* timer */
+ scb_s->cputm = scb_o->cputm;
+ scb_s->ckc = scb_o->ckc;
+ scb_s->todpr = scb_o->todpr;
+ scb_s->epoch = scb_o->epoch;
+
+ /* guest state */
+ scb_s->gpsw = scb_o->gpsw;
+ scb_s->gg14 = scb_o->gg14;
+ scb_s->gg15 = scb_o->gg15;
+ memcpy(scb_s->gcr, scb_o->gcr, 128);
+ scb_s->pp = scb_o->pp;
+
+ /* interception / execution handling */
+ scb_s->gbea = scb_o->gbea;
+ scb_s->lctl = scb_o->lctl;
+ scb_s->svcc = scb_o->svcc;
+ scb_s->ictl = scb_o->ictl;
+ /*
+ * SKEY handling functions can't deal with false setting of PTE invalid
+ * bits. Therefore we cannot provide interpretation and would later
+ * have to provide own emulation handlers.
+ */
+ scb_s->ictl |= ICTL_ISKE | ICTL_SSKE | ICTL_RRBE;
+ scb_s->icpua = scb_o->icpua;
+
+ /* SIE will do mso/msl validity and exception checks for us */
+ scb_s->msl = scb_o->msl & 0xfffffffffff00000UL;
+ scb_s->mso = scb_o->mso & 0xfffffffffff00000UL;
+ scb_s->prefix = scb_o->prefix;
+
+ /* We have to definetly flush the tlb if this scb never ran */
+ if (scb_s->ihcpu != 0xffffU)
+ scb_s->ihcpu = scb_o->ihcpu;
+
+ /* MVPG and Protection Exception Interpretation are always available */
+ scb_s->eca |= scb_o->eca & 0x01002000U;
+
+out:
+ if (rc)
+ unshadow_scb(vcpu, vsie_page);
+ return rc;
+}
+
+void kvm_s390_vsie_gmap_notifier(struct gmap *gmap, unsigned long start,
+ unsigned long end)
+{
+ struct kvm *kvm = gmap->private;
+ struct vsie_page *cur;
+ unsigned long prefix;
+ struct page *page;
+ int i;
+
+ if (!gmap_is_shadow(gmap))
+ return;
+ if (start >= 1UL << 31)
+ /* We are only interested in prefix pages */
+ return;
+
+ /*
+ * Only new shadow blocks are added to the list during runtime,
+ * therefore we can safely reference them all the time.
+ */
+ for (i = 0; i < kvm->arch.vsie.page_count; i++) {
+ page = READ_ONCE(kvm->arch.vsie.pages[i]);
+ if (!page)
+ continue;
+ cur = page_to_virt(page);
+ if (READ_ONCE(cur->gmap) != gmap)
+ continue;
+ prefix = cur->scb_s.prefix << GUEST_PREFIX_SHIFT;
+ /* with mso/msl, the prefix lies at an offset */
+ prefix += cur->scb_s.mso;
+ if (prefix <= end && start <= prefix + PAGE_SIZE - 1)
+ prefix_unmapped_sync(cur);
+ }
+}
+
+/*
+ * Map the first prefix page.
+ *
+ * The prefix will be protected, a gmap notifier will inform about unmaps.
+ * The shadow scb must not be executed until the prefix is remapped, this is
+ * guaranteed by properly handling PROG_REQUEST.
+ *
+ * Returns: - 0 on if successfully mapped or already mapped
+ * - > 0 if control has to be given to guest 2
+ * - -EAGAIN if the caller can retry immediately
+ * - -ENOMEM if out of memory
+ */
+static int map_prefix(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
+{
+ struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s;
+ u64 prefix = scb_s->prefix << GUEST_PREFIX_SHIFT;
+ int rc;
+
+ /* mark it as mapped so we can catch any concurrent unmappers */
+ prefix_mapped(vsie_page);
+
+ /* with mso/msl, the prefix lies at offset *mso* */
+ prefix += scb_s->mso;
+
+ rc = kvm_s390_shadow_fault(vcpu, vsie_page->gmap, prefix);
+ /*
+ * We don't have to mprotect, we will be called for all unshadows.
+ * SIE will detect if protection applies and trigger a validity.
+ */
+ if (rc)
+ prefix_unmapped(vsie_page);
+ if (rc > 0 || rc == -EFAULT)
+ rc = set_validity_icpt(scb_s, 0x0037U);
+ return rc;
+}
+
+/*
+ * Pin the guest page given by gpa and set hpa to the pinned host address.
+ * Will always be pinned writable.
+ *
+ * Returns: - 0 on success
+ * - -EINVAL if the gpa is not valid guest storage
+ * - -ENOMEM if out of memory
+ */
+static int pin_guest_page(struct kvm *kvm, gpa_t gpa, hpa_t *hpa)
+{
+ struct page *page;
+ hva_t hva;
+ int rc;
+
+ hva = gfn_to_hva(kvm, gpa_to_gfn(gpa));
+ if (kvm_is_error_hva(hva))
+ return -EINVAL;
+ rc = get_user_pages_fast(hva, 1, 1, &page);
+ if (rc < 0)
+ return rc;
+ else if (rc != 1)
+ return -ENOMEM;
+ *hpa = (hpa_t) page_to_virt(page) + (gpa & ~PAGE_MASK);
+ return 0;
+}
+
+/* Unpins a page previously pinned via pin_guest_page, marking it as dirty. */
+static void unpin_guest_page(struct kvm *kvm, gpa_t gpa, hpa_t hpa)
+{
+ struct page *page;
+
+ page = virt_to_page(hpa);
+ set_page_dirty_lock(page);
+ put_page(page);
+ /* mark the page always as dirty for migration */
+ mark_page_dirty(kvm, gpa_to_gfn(gpa));
+}
+
+/* unpin all blocks previously pinned by pin_blocks(), marking them dirty */
+static void unpin_blocks(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
+{
+ struct kvm_s390_sie_block *scb_o = vsie_page->scb_o;
+ struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s;
+ hpa_t hpa;
+ gpa_t gpa;
+
+ hpa = (u64) scb_s->scaoh << 32 | scb_s->scaol;
+ if (hpa) {
+ gpa = scb_o->scaol & ~0xfUL;
+ unpin_guest_page(vcpu->kvm, gpa, hpa);
+ scb_s->scaol = 0;
+ scb_s->scaoh = 0;
+ }
+}
+
+/*
+ * Instead of shadowing some blocks, we can simply forward them because the
+ * addresses in the scb are 64 bit long.
+ *
+ * This works as long as the data lies in one page. If blocks ever exceed one
+ * page, we have to fall back to shadowing.
+ *
+ * As we reuse the sca, the vcpu pointers contained in it are invalid. We must
+ * therefore not enable any facilities that access these pointers (e.g. SIGPIF).
+ *
+ * Returns: - 0 if all blocks were pinned.
+ * - > 0 if control has to be given to guest 2
+ * - -ENOMEM if out of memory
+ */
+static int pin_blocks(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
+{
+ struct kvm_s390_sie_block *scb_o = vsie_page->scb_o;
+ struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s;
+ hpa_t hpa;
+ gpa_t gpa;
+ int rc = 0;
+
+ gpa = scb_o->scaol & ~0xfUL;
+ if (gpa) {
+ if (!(gpa & ~0x1fffUL))
+ rc = set_validity_icpt(scb_s, 0x0038U);
+ else if ((gpa & ~0x1fffUL) == kvm_s390_get_prefix(vcpu))
+ rc = set_validity_icpt(scb_s, 0x0011U);
+ else if ((gpa & PAGE_MASK) !=
+ ((gpa + sizeof(struct bsca_block) - 1) & PAGE_MASK))
+ rc = set_validity_icpt(scb_s, 0x003bU);
+ if (!rc) {
+ rc = pin_guest_page(vcpu->kvm, gpa, &hpa);
+ if (rc == -EINVAL)
+ rc = set_validity_icpt(scb_s, 0x0034U);
+ }
+ if (rc)
+ goto unpin;
+ scb_s->scaoh = (u32)((u64)hpa >> 32);
+ scb_s->scaol = (u32)(u64)hpa;
+ }
+ return 0;
+unpin:
+ unpin_blocks(vcpu, vsie_page);
+ return rc;
+}
+
+/* unpin the scb provided by guest 2, marking it as dirty */
+static void unpin_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page,
+ gpa_t gpa)
+{
+ hpa_t hpa = (hpa_t) vsie_page->scb_o;
+
+ if (hpa)
+ unpin_guest_page(vcpu->kvm, gpa, hpa);
+ vsie_page->scb_o = NULL;
+}
+
+/*
+ * Pin the scb at gpa provided by guest 2 at vsie_page->scb_o.
+ *
+ * Returns: - 0 if the scb was pinned.
+ * - > 0 if control has to be given to guest 2
+ * - -ENOMEM if out of memory
+ */
+static int pin_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page,
+ gpa_t gpa)
+{
+ hpa_t hpa;
+ int rc;
+
+ rc = pin_guest_page(vcpu->kvm, gpa, &hpa);
+ if (rc == -EINVAL) {
+ rc = kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING);
+ if (!rc)
+ rc = 1;
+ }
+ if (!rc)
+ vsie_page->scb_o = (struct kvm_s390_sie_block *) hpa;
+ return rc;
+}
+
+/*
+ * Inject a fault into guest 2.
+ *
+ * Returns: - > 0 if control has to be given to guest 2
+ * < 0 if an error occurred during injection.
+ */
+static int inject_fault(struct kvm_vcpu *vcpu, __u16 code, __u64 vaddr,
+ bool write_flag)
+{
+ struct kvm_s390_pgm_info pgm = {
+ .code = code,
+ .trans_exc_code =
+ /* 0-51: virtual address */
+ (vaddr & 0xfffffffffffff000UL) |
+ /* 52-53: store / fetch */
+ (((unsigned int) !write_flag) + 1) << 10,
+ /* 62-63: asce id (alway primary == 0) */
+ .exc_access_id = 0, /* always primary */
+ .op_access_id = 0, /* not MVPG */
+ };
+ int rc;
+
+ if (code == PGM_PROTECTION)
+ pgm.trans_exc_code |= 0x4UL;
+
+ rc = kvm_s390_inject_prog_irq(vcpu, &pgm);
+ return rc ? rc : 1;
+}
+
+/*
+ * Handle a fault during vsie execution on a gmap shadow.
+ *
+ * Returns: - 0 if the fault was resolved
+ * - > 0 if control has to be given to guest 2
+ * - < 0 if an error occurred
+ */
+static int handle_fault(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
+{
+ int rc;
+
+ if (current->thread.gmap_int_code == PGM_PROTECTION)
+ /* we can directly forward all protection exceptions */
+ return inject_fault(vcpu, PGM_PROTECTION,
+ current->thread.gmap_addr, 1);
+
+ rc = kvm_s390_shadow_fault(vcpu, vsie_page->gmap,
+ current->thread.gmap_addr);
+ if (rc > 0) {
+ rc = inject_fault(vcpu, rc,
+ current->thread.gmap_addr,
+ current->thread.gmap_write_flag);
+ }
+ return rc;
+}
+
+static inline void clear_vsie_icpt(struct vsie_page *vsie_page)
+{
+ vsie_page->scb_s.icptcode = 0;
+}
+
+/*
+ * Run the vsie on a shadow scb and a shadow gmap, without any further
+ * sanity checks, handling SIE faults.
+ *
+ * Returns: - 0 everything went fine
+ * - > 0 if control has to be given to guest 2
+ * - < 0 if an error occurred
+ */
+static int do_vsie_run(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
+{
+ struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s;
+ struct kvm_s390_sie_block *scb_o = vsie_page->scb_o;
+ int rc;
+
+ if (need_resched())
+ schedule();
+ if (test_cpu_flag(CIF_MCCK_PENDING))
+ s390_handle_mcck();
+
+ srcu_read_unlock(&vcpu->kvm->srcu, vcpu->srcu_idx);
+ local_irq_disable();
+ kvm_guest_enter();
+ local_irq_enable();
+
+ rc = sie64a(scb_s, vcpu->run->s.regs.gprs);
+
+ local_irq_disable();
+ kvm_guest_exit();
+ local_irq_enable();
+ vcpu->srcu_idx = srcu_read_lock(&vcpu->kvm->srcu);
+
+ if (rc > 0)
+ rc = 0; /* we could still have an icpt */
+ else if (rc == -EFAULT)
+ return handle_fault(vcpu, vsie_page);
+
+ switch (scb_s->icptcode) {
+ case ICPT_STOP:
+ /* stop not requested by g2 - must have been a kick */
+ if (!(atomic_read(&scb_o->cpuflags) & CPUSTAT_STOP_INT))
+ clear_vsie_icpt(vsie_page);
+ break;
+ case ICPT_VALIDITY:
+ if ((scb_s->ipa & 0xf000) != 0xf000)
+ scb_s->ipa += 0x1000;
+ break;
+ }
+ return rc;
+}
+
+static void release_gmap_shadow(struct vsie_page *vsie_page)
+{
+ if (vsie_page->gmap)
+ gmap_put(vsie_page->gmap);
+ WRITE_ONCE(vsie_page->gmap, NULL);
+}
+
+static int acquire_gmap_shadow(struct kvm_vcpu *vcpu,
+ struct vsie_page *vsie_page)
+{
+ unsigned long asce;
+ union ctlreg0 cr0;
+ struct gmap *gmap;
+ int edat;
+
+ asce = vcpu->arch.sie_block->gcr[1];
+ cr0.val = vcpu->arch.sie_block->gcr[0];
+ edat = cr0.edat && test_kvm_facility(vcpu->kvm, 8);
+ edat += edat && test_kvm_facility(vcpu->kvm, 78);
+
+ gmap = gmap_shadow(vcpu->arch.gmap, asce, edat);
+ if (IS_ERR(gmap))
+ return PTR_ERR(gmap);
+ gmap->private = vcpu->kvm;
+ WRITE_ONCE(vsie_page->gmap, gmap);
+ return 0;
+}
+
+/*
+ * Run the vsie on a shadowed scb, managing the gmap shadow, handling
+ * prefix pages and faults.
+ *
+ * Returns: - 0 if no errors occurred
+ * - > 0 if control has to be given to guest 2
+ * - -ENOMEM if out of memory
+ */
+static int vsie_run(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
+{
+ struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s;
+ int rc = 0;
+
+ while (1) {
+ rc = acquire_gmap_shadow(vcpu, vsie_page);
+ if (!rc)
+ rc = map_prefix(vcpu, vsie_page);
+ if (!rc) {
+ gmap_enable(vsie_page->gmap);
+ update_intervention_requests(vsie_page);
+ rc = do_vsie_run(vcpu, vsie_page);
+ gmap_enable(vcpu->arch.gmap);
+ }
+ release_gmap_shadow(vsie_page);
+
+ if (rc == -EAGAIN)
+ rc = 0;
+ if (rc || scb_s->icptcode || signal_pending(current) ||
+ kvm_s390_vcpu_has_irq(vcpu, 0))
+ break;
+ };
+
+ if (rc == -EFAULT) {
+ /*
+ * Addressing exceptions are always presentes as intercepts.
+ * As addressing exceptions are suppressing and our guest 3 PSW
+ * points at the responsible instruction, we have to
+ * forward the PSW and set the ilc. If we can't read guest 3
+ * instruction, we can use an arbitrary ilc. Let's always use
+ * ilen = 4 for now, so we can avoid reading in guest 3 virtual
+ * memory. (we could also fake the shadow so the hardware
+ * handles it).
+ */
+ scb_s->icptcode = ICPT_PROGI;
+ scb_s->iprcc = PGM_ADDRESSING;
+ scb_s->pgmilc = 4;
+ scb_s->gpsw.addr = __rewind_psw(scb_s->gpsw, 4);
+ }
+ return rc;
+}
+
+/*
+ * Get or create a vsie page for a scb address.
+ *
+ * Returns: - address of a vsie page (cached or new one)
+ * - NULL if the same scb address is already used by another VCPU
+ * - ERR_PTR(-ENOMEM) if out of memory
+ */
+static struct vsie_page *get_vsie_page(struct kvm *kvm, unsigned long addr)
+{
+ struct vsie_page *vsie_page;
+ struct page *page;
+ int nr_vcpus;
+
+ rcu_read_lock();
+ page = radix_tree_lookup(&kvm->arch.vsie.addr_to_page, addr >> 9);
+ rcu_read_unlock();
+ if (page) {
+ if (page_ref_inc_return(page) == 2)
+ return page_to_virt(page);
+ page_ref_dec(page);
+ }
+
+ /*
+ * We want at least #online_vcpus shadows, so every VCPU can execute
+ * the VSIE in parallel.
+ */
+ nr_vcpus = atomic_read(&kvm->online_vcpus);
+
+ mutex_lock(&kvm->arch.vsie.mutex);
+ if (kvm->arch.vsie.page_count < nr_vcpus) {
+ page = alloc_page(GFP_KERNEL | __GFP_ZERO);
+ if (!page) {
+ mutex_unlock(&kvm->arch.vsie.mutex);
+ return ERR_PTR(-ENOMEM);
+ }
+ page_ref_inc(page);
+ kvm->arch.vsie.pages[kvm->arch.vsie.page_count] = page;
+ kvm->arch.vsie.page_count++;
+ } else {
+ /* reuse an existing entry that belongs to nobody */
+ while (true) {
+ page = kvm->arch.vsie.pages[kvm->arch.vsie.next];
+ if (page_ref_inc_return(page) == 2)
+ break;
+ page_ref_dec(page);
+ kvm->arch.vsie.next++;
+ kvm->arch.vsie.next %= nr_vcpus;
+ }
+ radix_tree_delete(&kvm->arch.vsie.addr_to_page, page->index >> 9);
+ }
+ page->index = addr;
+ /* double use of the same address */
+ if (radix_tree_insert(&kvm->arch.vsie.addr_to_page, addr >> 9, page)) {
+ page_ref_dec(page);
+ mutex_unlock(&kvm->arch.vsie.mutex);
+ return NULL;
+ }
+ mutex_unlock(&kvm->arch.vsie.mutex);
+
+ vsie_page = page_to_virt(page);
+ memset(&vsie_page->scb_s, 0, sizeof(struct kvm_s390_sie_block));
+ vsie_page->scb_s.ihcpu = 0xffffU;
+ return vsie_page;
+}
+
+/* put a vsie page acquired via get_vsie_page */
+static void put_vsie_page(struct kvm *kvm, struct vsie_page *vsie_page)
+{
+ struct page *page = pfn_to_page(__pa(vsie_page) >> PAGE_SHIFT);
+
+ page_ref_dec(page);
+}
+
+int kvm_s390_handle_vsie(struct kvm_vcpu *vcpu)
+{
+ struct vsie_page *vsie_page;
+ unsigned long scb_addr;
+ int rc;
+
+ vcpu->stat.instruction_sie++;
+ if (!test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_SIEF2))
+ return -EOPNOTSUPP;
+ if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
+ return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP);
+
+ BUILD_BUG_ON(sizeof(struct vsie_page) != 4096);
+ scb_addr = kvm_s390_get_base_disp_s(vcpu, NULL);
+
+ /* 512 byte alignment */
+ if (unlikely(scb_addr & 0x1ffUL))
+ return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
+
+ if (signal_pending(current) || kvm_s390_vcpu_has_irq(vcpu, 0))
+ return 0;
+
+ vsie_page = get_vsie_page(vcpu->kvm, scb_addr);
+ if (IS_ERR(vsie_page))
+ return PTR_ERR(vsie_page);
+ else if (!vsie_page)
+ /* double use of sie control block - simply do nothing */
+ return 0;
+
+ rc = pin_scb(vcpu, vsie_page, scb_addr);
+ if (rc)
+ goto out_put;
+ rc = shadow_scb(vcpu, vsie_page);
+ if (rc)
+ goto out_unpin_scb;
+ rc = pin_blocks(vcpu, vsie_page);
+ if (rc)
+ goto out_unshadow;
+ rc = vsie_run(vcpu, vsie_page);
+ unpin_blocks(vcpu, vsie_page);
+out_unshadow:
+ unshadow_scb(vcpu, vsie_page);
+out_unpin_scb:
+ unpin_scb(vcpu, vsie_page, scb_addr);
+out_put:
+ put_vsie_page(vcpu->kvm, vsie_page);
+
+ return rc < 0 ? rc : 0;
+}
+
+/* Init the vsie data structures. To be called when a vm is initialized. */
+void kvm_s390_vsie_init(struct kvm *kvm)
+{
+ mutex_init(&kvm->arch.vsie.mutex);
+ INIT_RADIX_TREE(&kvm->arch.vsie.addr_to_page, GFP_KERNEL);
+}
+
+/* Destroy the vsie data structures. To be called when a vm is destroyed. */
+void kvm_s390_vsie_destroy(struct kvm *kvm)
+{
+ struct page *page;
+ int i;
+
+ mutex_lock(&kvm->arch.vsie.mutex);
+ for (i = 0; i < kvm->arch.vsie.page_count; i++) {
+ page = kvm->arch.vsie.pages[i];
+ kvm->arch.vsie.pages[i] = NULL;
+ /* free the radix tree entry */
+ radix_tree_delete(&kvm->arch.vsie.addr_to_page, page->index >> 9);
+ __free_page(page);
+ }
+ kvm->arch.vsie.page_count = 0;
+ mutex_unlock(&kvm->arch.vsie.mutex);
+}
--
2.5.5
^ permalink raw reply related [flat|nested] 53+ messages in thread* [GIT PULL 29/51] KVM: s390: vsie: optimize gmap prefix mapping
2016-06-21 13:12 [GIT PULL 00/51] KVM: s390: vSIE (nested virtualization) feature for 4.8 (kvm/next) Christian Borntraeger
` (27 preceding siblings ...)
2016-06-21 13:13 ` [GIT PULL 28/51] KVM: s390: vsie: initial support for nested virtualization Christian Borntraeger
@ 2016-06-21 13:13 ` Christian Borntraeger
2016-06-21 13:13 ` [GIT PULL 30/51] KVM: s390: vsie: support setting the ibc Christian Borntraeger
` (22 subsequent siblings)
51 siblings, 0 replies; 53+ messages in thread
From: Christian Borntraeger @ 2016-06-21 13:13 UTC (permalink / raw)
To: Paolo Bonzini, Radim Krčmář
Cc: KVM, Cornelia Huck, linux-s390, Christian Borntraeger,
David Hildenbrand, Martin Schwidefsky
From: David Hildenbrand <dahi@linux.vnet.ibm.com>
In order to not always map the prefix, we have to take care of certain
aspects that implicitly unmap the prefix:
- Changes to the prefix address
- Changes to MSO, because the HVA of the prefix is changed
- Changes of the gmap shadow (e.g. unshadowed, asce or edat changes)
By properly handling these cases, we can stop remapping the prefix when
there is no reason to do so.
This also allows us now to not acquire any gmap shadow locks when
rerunning the vsie and still having a valid gmap shadow.
Please note, to detect changing gmap shadows, we have to keep the reference
of the gmap shadow. The address of a gmap shadow does otherwise not
reliably indicate if the gmap shadow has changed (the memory chunk
could get reused).
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
arch/s390/kvm/vsie.c | 31 +++++++++++++++++++++++++++++--
1 file changed, 29 insertions(+), 2 deletions(-)
diff --git a/arch/s390/kvm/vsie.c b/arch/s390/kvm/vsie.c
index 747d4f9..2839efc 100644
--- a/arch/s390/kvm/vsie.c
+++ b/arch/s390/kvm/vsie.c
@@ -62,6 +62,11 @@ static void prefix_mapped(struct vsie_page *vsie_page)
atomic_andnot(PROG_REQUEST, &vsie_page->scb_s.prog20);
}
+/* test if the prefix is mapped into the gmap shadow */
+static int prefix_is_mapped(struct vsie_page *vsie_page)
+{
+ return !(atomic_read(&vsie_page->scb_s.prog20) & PROG_REQUEST);
+}
/* copy the updated intervention request bits into the shadow scb */
static void update_intervention_requests(struct vsie_page *vsie_page)
@@ -152,6 +157,7 @@ static int shadow_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
{
struct kvm_s390_sie_block *scb_o = vsie_page->scb_o;
struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s;
+ unsigned long new_mso;
int rc;
/* make sure we don't have any leftovers when reusing the scb */
@@ -192,9 +198,13 @@ static int shadow_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
scb_s->ictl |= ICTL_ISKE | ICTL_SSKE | ICTL_RRBE;
scb_s->icpua = scb_o->icpua;
+ new_mso = scb_o->mso & 0xfffffffffff00000UL;
+ /* if the hva of the prefix changes, we have to remap the prefix */
+ if (scb_s->mso != new_mso || scb_s->prefix != scb_o->prefix)
+ prefix_unmapped(vsie_page);
/* SIE will do mso/msl validity and exception checks for us */
scb_s->msl = scb_o->msl & 0xfffffffffff00000UL;
- scb_s->mso = scb_o->mso & 0xfffffffffff00000UL;
+ scb_s->mso = new_mso;
scb_s->prefix = scb_o->prefix;
/* We have to definetly flush the tlb if this scb never ran */
@@ -262,6 +272,9 @@ static int map_prefix(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
u64 prefix = scb_s->prefix << GUEST_PREFIX_SHIFT;
int rc;
+ if (prefix_is_mapped(vsie_page))
+ return 0;
+
/* mark it as mapped so we can catch any concurrent unmappers */
prefix_mapped(vsie_page);
@@ -532,6 +545,7 @@ static void release_gmap_shadow(struct vsie_page *vsie_page)
if (vsie_page->gmap)
gmap_put(vsie_page->gmap);
WRITE_ONCE(vsie_page->gmap, NULL);
+ prefix_unmapped(vsie_page);
}
static int acquire_gmap_shadow(struct kvm_vcpu *vcpu,
@@ -547,6 +561,16 @@ static int acquire_gmap_shadow(struct kvm_vcpu *vcpu,
edat = cr0.edat && test_kvm_facility(vcpu->kvm, 8);
edat += edat && test_kvm_facility(vcpu->kvm, 78);
+ /*
+ * ASCE or EDAT could have changed since last icpt, or the gmap
+ * we're holding has been unshadowed. If the gmap is still valid,
+ * we can safely reuse it.
+ */
+ if (vsie_page->gmap && gmap_shadow_valid(vsie_page->gmap, asce, edat))
+ return 0;
+
+ /* release the old shadow - if any, and mark the prefix as unmapped */
+ release_gmap_shadow(vsie_page);
gmap = gmap_shadow(vcpu->arch.gmap, asce, edat);
if (IS_ERR(gmap))
return PTR_ERR(gmap);
@@ -578,7 +602,6 @@ static int vsie_run(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
rc = do_vsie_run(vcpu, vsie_page);
gmap_enable(vcpu->arch.gmap);
}
- release_gmap_shadow(vsie_page);
if (rc == -EAGAIN)
rc = 0;
@@ -667,6 +690,7 @@ static struct vsie_page *get_vsie_page(struct kvm *kvm, unsigned long addr)
vsie_page = page_to_virt(page);
memset(&vsie_page->scb_s, 0, sizeof(struct kvm_s390_sie_block));
+ release_gmap_shadow(vsie_page);
vsie_page->scb_s.ihcpu = 0xffffU;
return vsie_page;
}
@@ -739,6 +763,7 @@ void kvm_s390_vsie_init(struct kvm *kvm)
/* Destroy the vsie data structures. To be called when a vm is destroyed. */
void kvm_s390_vsie_destroy(struct kvm *kvm)
{
+ struct vsie_page *vsie_page;
struct page *page;
int i;
@@ -746,6 +771,8 @@ void kvm_s390_vsie_destroy(struct kvm *kvm)
for (i = 0; i < kvm->arch.vsie.page_count; i++) {
page = kvm->arch.vsie.pages[i];
kvm->arch.vsie.pages[i] = NULL;
+ vsie_page = page_to_virt(page);
+ release_gmap_shadow(vsie_page);
/* free the radix tree entry */
radix_tree_delete(&kvm->arch.vsie.addr_to_page, page->index >> 9);
__free_page(page);
--
2.5.5
^ permalink raw reply related [flat|nested] 53+ messages in thread* [GIT PULL 30/51] KVM: s390: vsie: support setting the ibc
2016-06-21 13:12 [GIT PULL 00/51] KVM: s390: vSIE (nested virtualization) feature for 4.8 (kvm/next) Christian Borntraeger
` (28 preceding siblings ...)
2016-06-21 13:13 ` [GIT PULL 29/51] KVM: s390: vsie: optimize gmap prefix mapping Christian Borntraeger
@ 2016-06-21 13:13 ` Christian Borntraeger
2016-06-21 13:13 ` [GIT PULL 31/51] KVM: s390: vsie: support edat1 / edat2 Christian Borntraeger
` (21 subsequent siblings)
51 siblings, 0 replies; 53+ messages in thread
From: Christian Borntraeger @ 2016-06-21 13:13 UTC (permalink / raw)
To: Paolo Bonzini, Radim Krčmář
Cc: KVM, Cornelia Huck, linux-s390, Christian Borntraeger,
David Hildenbrand, Martin Schwidefsky
From: David Hildenbrand <dahi@linux.vnet.ibm.com>
As soon as we forward an ibc to guest 2 (indicated via
kvm->arch.model.ibc), he can also use it for guest 3. Let's properly round
the ibc up/down, so we avoid any potential validity icpts from the
underlying SIE, if it doesn't simply round the values.
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
arch/s390/kvm/vsie.c | 21 +++++++++++++++++++++
1 file changed, 21 insertions(+)
diff --git a/arch/s390/kvm/vsie.c b/arch/s390/kvm/vsie.c
index 2839efc..1165baf 100644
--- a/arch/s390/kvm/vsie.c
+++ b/arch/s390/kvm/vsie.c
@@ -102,6 +102,26 @@ static int prepare_cpuflags(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
return 0;
}
+/* shadow (round up/down) the ibc to avoid validity icpt */
+static void prepare_ibc(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
+{
+ struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s;
+ struct kvm_s390_sie_block *scb_o = vsie_page->scb_o;
+ __u64 min_ibc = (sclp.ibc >> 16) & 0x0fffU;
+
+ scb_s->ibc = 0;
+ /* ibc installed in g2 and requested for g3 */
+ if (vcpu->kvm->arch.model.ibc && (scb_o->ibc & 0x0fffU)) {
+ scb_s->ibc = scb_o->ibc & 0x0fffU;
+ /* takte care of the minimum ibc level of the machine */
+ if (scb_s->ibc < min_ibc)
+ scb_s->ibc = min_ibc;
+ /* take care of the maximum ibc level set for the guest */
+ if (scb_s->ibc > vcpu->kvm->arch.model.ibc)
+ scb_s->ibc = vcpu->kvm->arch.model.ibc;
+ }
+}
+
/* unshadow the scb, copying parameters back to the real scb */
static void unshadow_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
{
@@ -214,6 +234,7 @@ static int shadow_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
/* MVPG and Protection Exception Interpretation are always available */
scb_s->eca |= scb_o->eca & 0x01002000U;
+ prepare_ibc(vcpu, vsie_page);
out:
if (rc)
unshadow_scb(vcpu, vsie_page);
--
2.5.5
^ permalink raw reply related [flat|nested] 53+ messages in thread* [GIT PULL 31/51] KVM: s390: vsie: support edat1 / edat2
2016-06-21 13:12 [GIT PULL 00/51] KVM: s390: vSIE (nested virtualization) feature for 4.8 (kvm/next) Christian Borntraeger
` (29 preceding siblings ...)
2016-06-21 13:13 ` [GIT PULL 30/51] KVM: s390: vsie: support setting the ibc Christian Borntraeger
@ 2016-06-21 13:13 ` Christian Borntraeger
2016-06-21 13:13 ` [GIT PULL 32/51] KVM: s390: vsie: support host-protection-interruption Christian Borntraeger
` (20 subsequent siblings)
51 siblings, 0 replies; 53+ messages in thread
From: Christian Borntraeger @ 2016-06-21 13:13 UTC (permalink / raw)
To: Paolo Bonzini, Radim Krčmář
Cc: KVM, Cornelia Huck, linux-s390, Christian Borntraeger,
David Hildenbrand, Martin Schwidefsky
From: David Hildenbrand <dahi@linux.vnet.ibm.com>
If guest 2 is allowed to use edat 1 / edat 2, it can also set it up for
guest 3, so let's properly check and forward the edat cpuflags.
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
arch/s390/kvm/vsie.c | 7 +++++++
1 file changed, 7 insertions(+)
diff --git a/arch/s390/kvm/vsie.c b/arch/s390/kvm/vsie.c
index 1165baf..7c9835b 100644
--- a/arch/s390/kvm/vsie.c
+++ b/arch/s390/kvm/vsie.c
@@ -97,6 +97,13 @@ static int prepare_cpuflags(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
/* intervention requests will be set later */
newflags = CPUSTAT_ZARCH;
+ if (cpuflags & CPUSTAT_GED && test_kvm_facility(vcpu->kvm, 8))
+ newflags |= CPUSTAT_GED;
+ if (cpuflags & CPUSTAT_GED2 && test_kvm_facility(vcpu->kvm, 78)) {
+ if (cpuflags & CPUSTAT_GED)
+ return set_validity_icpt(scb_s, 0x0001U);
+ newflags |= CPUSTAT_GED2;
+ }
atomic_set(&scb_s->cpuflags, newflags);
return 0;
--
2.5.5
^ permalink raw reply related [flat|nested] 53+ messages in thread* [GIT PULL 32/51] KVM: s390: vsie: support host-protection-interruption
2016-06-21 13:12 [GIT PULL 00/51] KVM: s390: vSIE (nested virtualization) feature for 4.8 (kvm/next) Christian Borntraeger
` (30 preceding siblings ...)
2016-06-21 13:13 ` [GIT PULL 31/51] KVM: s390: vsie: support edat1 / edat2 Christian Borntraeger
@ 2016-06-21 13:13 ` Christian Borntraeger
2016-06-21 13:13 ` [GIT PULL 33/51] KVM: s390: vsie: support STFLE interpretation Christian Borntraeger
` (19 subsequent siblings)
51 siblings, 0 replies; 53+ messages in thread
From: Christian Borntraeger @ 2016-06-21 13:13 UTC (permalink / raw)
To: Paolo Bonzini, Radim Krčmář
Cc: KVM, Cornelia Huck, linux-s390, Christian Borntraeger,
David Hildenbrand, Martin Schwidefsky
From: David Hildenbrand <dahi@linux.vnet.ibm.com>
Introduced with ESOP, therefore available for the guest if it
is allowed to use ESOP.
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
arch/s390/kvm/vsie.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/arch/s390/kvm/vsie.c b/arch/s390/kvm/vsie.c
index 7c9835b..aaed63c 100644
--- a/arch/s390/kvm/vsie.c
+++ b/arch/s390/kvm/vsie.c
@@ -240,6 +240,9 @@ static int shadow_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
/* MVPG and Protection Exception Interpretation are always available */
scb_s->eca |= scb_o->eca & 0x01002000U;
+ /* Host-protection-interruption introduced with ESOP */
+ if (test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_ESOP))
+ scb_s->ecb |= scb_o->ecb & 0x02U;
prepare_ibc(vcpu, vsie_page);
out:
--
2.5.5
^ permalink raw reply related [flat|nested] 53+ messages in thread* [GIT PULL 33/51] KVM: s390: vsie: support STFLE interpretation
2016-06-21 13:12 [GIT PULL 00/51] KVM: s390: vSIE (nested virtualization) feature for 4.8 (kvm/next) Christian Borntraeger
` (31 preceding siblings ...)
2016-06-21 13:13 ` [GIT PULL 32/51] KVM: s390: vsie: support host-protection-interruption Christian Borntraeger
@ 2016-06-21 13:13 ` Christian Borntraeger
2016-06-21 13:13 ` [GIT PULL 34/51] KVM: s390: vsie: support aes dea wrapping keys Christian Borntraeger
` (18 subsequent siblings)
51 siblings, 0 replies; 53+ messages in thread
From: Christian Borntraeger @ 2016-06-21 13:13 UTC (permalink / raw)
To: Paolo Bonzini, Radim Krčmář
Cc: KVM, Cornelia Huck, linux-s390, Christian Borntraeger,
David Hildenbrand, Martin Schwidefsky
From: David Hildenbrand <dahi@linux.vnet.ibm.com>
Issuing STFLE is extremely rare. Instead of copying 2k on every
VSIE call, let's do this lazily, when a guest 3 tries to execute
STFLE. We can setup the block and retry.
Unfortunately, we can't directly forward that facility list, as
we only have a 31 bit address for the facility list designation.
So let's use a DMA allocation for our vsie_page instead for now.
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
arch/s390/kvm/vsie.c | 49 +++++++++++++++++++++++++++++++++++++++++++++++--
1 file changed, 47 insertions(+), 2 deletions(-)
diff --git a/arch/s390/kvm/vsie.c b/arch/s390/kvm/vsie.c
index aaed63c..cd4bbfa 100644
--- a/arch/s390/kvm/vsie.c
+++ b/arch/s390/kvm/vsie.c
@@ -18,6 +18,7 @@
#include <asm/mmu_context.h>
#include <asm/sclp.h>
#include <asm/nmi.h>
+#include <asm/dis.h>
#include "kvm-s390.h"
#include "gaccess.h"
@@ -27,7 +28,8 @@ struct vsie_page {
struct kvm_s390_sie_block *scb_o; /* 0x0200 */
/* the shadow gmap in use by the vsie_page */
struct gmap *gmap; /* 0x0208 */
- __u8 reserved[0x1000 - 0x0210]; /* 0x0210 */
+ __u8 reserved[0x0800 - 0x0210]; /* 0x0210 */
+ __u8 fac[S390_ARCH_FAC_LIST_SIZE_BYTE]; /* 0x0800 */
} __packed;
/* trigger a validity icpt for the given scb */
@@ -194,6 +196,7 @@ static int shadow_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
scb_s->ecb2 = 0;
scb_s->ecb3 = 0;
scb_s->ecd = 0;
+ scb_s->fac = 0;
rc = prepare_cpuflags(vcpu, vsie_page);
if (rc)
@@ -521,6 +524,44 @@ static inline void clear_vsie_icpt(struct vsie_page *vsie_page)
vsie_page->scb_s.icptcode = 0;
}
+/* rewind the psw and clear the vsie icpt, so we can retry execution */
+static void retry_vsie_icpt(struct vsie_page *vsie_page)
+{
+ struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s;
+ int ilen = insn_length(scb_s->ipa >> 8);
+
+ /* take care of EXECUTE instructions */
+ if (scb_s->icptstatus & 1) {
+ ilen = (scb_s->icptstatus >> 4) & 0x6;
+ if (!ilen)
+ ilen = 4;
+ }
+ scb_s->gpsw.addr = __rewind_psw(scb_s->gpsw, ilen);
+ clear_vsie_icpt(vsie_page);
+}
+
+/*
+ * Try to shadow + enable the guest 2 provided facility list.
+ * Retry instruction execution if enabled for and provided by guest 2.
+ *
+ * Returns: - 0 if handled (retry or guest 2 icpt)
+ * - > 0 if control has to be given to guest 2
+ */
+static int handle_stfle(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
+{
+ struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s;
+ __u32 fac = vsie_page->scb_o->fac & 0x7ffffff8U;
+
+ if (fac && test_kvm_facility(vcpu->kvm, 7)) {
+ retry_vsie_icpt(vsie_page);
+ if (read_guest_real(vcpu, fac, &vsie_page->fac,
+ sizeof(vsie_page->fac)))
+ return set_validity_icpt(scb_s, 0x1090U);
+ scb_s->fac = (__u32)(__u64) &vsie_page->fac;
+ }
+ return 0;
+}
+
/*
* Run the vsie on a shadow scb and a shadow gmap, without any further
* sanity checks, handling SIE faults.
@@ -558,6 +599,10 @@ static int do_vsie_run(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
return handle_fault(vcpu, vsie_page);
switch (scb_s->icptcode) {
+ case ICPT_INST:
+ if (scb_s->ipa == 0xb2b0)
+ rc = handle_stfle(vcpu, vsie_page);
+ break;
case ICPT_STOP:
/* stop not requested by g2 - must have been a kick */
if (!(atomic_read(&scb_o->cpuflags) & CPUSTAT_STOP_INT))
@@ -690,7 +735,7 @@ static struct vsie_page *get_vsie_page(struct kvm *kvm, unsigned long addr)
mutex_lock(&kvm->arch.vsie.mutex);
if (kvm->arch.vsie.page_count < nr_vcpus) {
- page = alloc_page(GFP_KERNEL | __GFP_ZERO);
+ page = alloc_page(GFP_KERNEL | __GFP_ZERO | GFP_DMA);
if (!page) {
mutex_unlock(&kvm->arch.vsie.mutex);
return ERR_PTR(-ENOMEM);
--
2.5.5
^ permalink raw reply related [flat|nested] 53+ messages in thread* [GIT PULL 34/51] KVM: s390: vsie: support aes dea wrapping keys
2016-06-21 13:12 [GIT PULL 00/51] KVM: s390: vSIE (nested virtualization) feature for 4.8 (kvm/next) Christian Borntraeger
` (32 preceding siblings ...)
2016-06-21 13:13 ` [GIT PULL 33/51] KVM: s390: vsie: support STFLE interpretation Christian Borntraeger
@ 2016-06-21 13:13 ` Christian Borntraeger
2016-06-21 13:13 ` [GIT PULL 35/51] KVM: s390: vsie: support transactional execution Christian Borntraeger
` (17 subsequent siblings)
51 siblings, 0 replies; 53+ messages in thread
From: Christian Borntraeger @ 2016-06-21 13:13 UTC (permalink / raw)
To: Paolo Bonzini, Radim Krčmář
Cc: KVM, Cornelia Huck, linux-s390, Christian Borntraeger,
David Hildenbrand, Martin Schwidefsky
From: David Hildenbrand <dahi@linux.vnet.ibm.com>
As soon as message-security-assist extension 3 is enabled for guest 2,
we have to allow key wrapping for guest 3.
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
arch/s390/kvm/vsie.c | 56 +++++++++++++++++++++++++++++++++++++++++++++++++++-
1 file changed, 55 insertions(+), 1 deletion(-)
diff --git a/arch/s390/kvm/vsie.c b/arch/s390/kvm/vsie.c
index cd4bbfa..6b26b0b 100644
--- a/arch/s390/kvm/vsie.c
+++ b/arch/s390/kvm/vsie.c
@@ -28,7 +28,8 @@ struct vsie_page {
struct kvm_s390_sie_block *scb_o; /* 0x0200 */
/* the shadow gmap in use by the vsie_page */
struct gmap *gmap; /* 0x0208 */
- __u8 reserved[0x0800 - 0x0210]; /* 0x0210 */
+ __u8 reserved[0x0700 - 0x0210]; /* 0x0210 */
+ struct kvm_s390_crypto_cb crycb; /* 0x0700 */
__u8 fac[S390_ARCH_FAC_LIST_SIZE_BYTE]; /* 0x0800 */
} __packed;
@@ -111,6 +112,58 @@ static int prepare_cpuflags(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
return 0;
}
+/*
+ * Create a shadow copy of the crycb block and setup key wrapping, if
+ * requested for guest 3 and enabled for guest 2.
+ *
+ * We only accept format-1 (no AP in g2), but convert it into format-2
+ * There is nothing to do for format-0.
+ *
+ * Returns: - 0 if shadowed or nothing to do
+ * - > 0 if control has to be given to guest 2
+ */
+static int shadow_crycb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
+{
+ struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s;
+ struct kvm_s390_sie_block *scb_o = vsie_page->scb_o;
+ u32 crycb_addr = scb_o->crycbd & 0x7ffffff8U;
+ unsigned long *b1, *b2;
+ u8 ecb3_flags;
+
+ scb_s->crycbd = 0;
+ if (!(scb_o->crycbd & vcpu->arch.sie_block->crycbd & CRYCB_FORMAT1))
+ return 0;
+ /* format-1 is supported with message-security-assist extension 3 */
+ if (!test_kvm_facility(vcpu->kvm, 76))
+ return 0;
+ /* we may only allow it if enabled for guest 2 */
+ ecb3_flags = scb_o->ecb3 & vcpu->arch.sie_block->ecb3 &
+ (ECB3_AES | ECB3_DEA);
+ if (!ecb3_flags)
+ return 0;
+
+ if ((crycb_addr & PAGE_MASK) != ((crycb_addr + 128) & PAGE_MASK))
+ return set_validity_icpt(scb_s, 0x003CU);
+ else if (!crycb_addr)
+ return set_validity_icpt(scb_s, 0x0039U);
+
+ /* copy only the wrapping keys */
+ if (read_guest_real(vcpu, crycb_addr + 72, &vsie_page->crycb, 56))
+ return set_validity_icpt(scb_s, 0x0035U);
+
+ scb_s->ecb3 |= ecb3_flags;
+ scb_s->crycbd = ((__u32)(__u64) &vsie_page->crycb) | CRYCB_FORMAT1 |
+ CRYCB_FORMAT2;
+
+ /* xor both blocks in one run */
+ b1 = (unsigned long *) vsie_page->crycb.dea_wrapping_key_mask;
+ b2 = (unsigned long *)
+ vcpu->kvm->arch.crypto.crycb->dea_wrapping_key_mask;
+ /* as 56%8 == 0, bitmap_xor won't overwrite any data */
+ bitmap_xor(b1, b1, b2, BITS_PER_BYTE * 56);
+ return 0;
+}
+
/* shadow (round up/down) the ibc to avoid validity icpt */
static void prepare_ibc(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
{
@@ -248,6 +301,7 @@ static int shadow_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
scb_s->ecb |= scb_o->ecb & 0x02U;
prepare_ibc(vcpu, vsie_page);
+ rc = shadow_crycb(vcpu, vsie_page);
out:
if (rc)
unshadow_scb(vcpu, vsie_page);
--
2.5.5
^ permalink raw reply related [flat|nested] 53+ messages in thread* [GIT PULL 35/51] KVM: s390: vsie: support transactional execution
2016-06-21 13:12 [GIT PULL 00/51] KVM: s390: vSIE (nested virtualization) feature for 4.8 (kvm/next) Christian Borntraeger
` (33 preceding siblings ...)
2016-06-21 13:13 ` [GIT PULL 34/51] KVM: s390: vsie: support aes dea wrapping keys Christian Borntraeger
@ 2016-06-21 13:13 ` Christian Borntraeger
2016-06-21 13:13 ` [GIT PULL 36/51] KVM: s390: vsie: support vectory facility (SIMD) Christian Borntraeger
` (16 subsequent siblings)
51 siblings, 0 replies; 53+ messages in thread
From: Christian Borntraeger @ 2016-06-21 13:13 UTC (permalink / raw)
To: Paolo Bonzini, Radim Krčmář
Cc: KVM, Cornelia Huck, linux-s390, Christian Borntraeger,
David Hildenbrand, Martin Schwidefsky
From: David Hildenbrand <dahi@linux.vnet.ibm.com>
As soon as guest 2 is allowed to use transactional execution (indicated via
STFLE), he can also enable it for guest 3.
Active transactional execution requires also the second prefix page to be
mapped. If that page cannot be mapped, a validity icpt has to be presented
to the guest.
We have to take care of tx being toggled on/off, otherwise we might get
wrong prefix validity icpt.
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
arch/s390/kvm/vsie.c | 37 +++++++++++++++++++++++++++++++++++--
1 file changed, 35 insertions(+), 2 deletions(-)
diff --git a/arch/s390/kvm/vsie.c b/arch/s390/kvm/vsie.c
index 6b26b0b..4e2c71c 100644
--- a/arch/s390/kvm/vsie.c
+++ b/arch/s390/kvm/vsie.c
@@ -239,6 +239,7 @@ static int shadow_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
{
struct kvm_s390_sie_block *scb_o = vsie_page->scb_o;
struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s;
+ bool had_tx = scb_s->ecb & 0x10U;
unsigned long new_mso;
int rc;
@@ -299,6 +300,13 @@ static int shadow_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
/* Host-protection-interruption introduced with ESOP */
if (test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_ESOP))
scb_s->ecb |= scb_o->ecb & 0x02U;
+ /* transactional execution */
+ if (test_kvm_facility(vcpu->kvm, 73)) {
+ /* remap the prefix is tx is toggled on */
+ if ((scb_o->ecb & 0x10U) && !had_tx)
+ prefix_unmapped(vsie_page);
+ scb_s->ecb |= scb_o->ecb & 0x10U;
+ }
prepare_ibc(vcpu, vsie_page);
rc = shadow_crycb(vcpu, vsie_page);
@@ -337,13 +345,13 @@ void kvm_s390_vsie_gmap_notifier(struct gmap *gmap, unsigned long start,
prefix = cur->scb_s.prefix << GUEST_PREFIX_SHIFT;
/* with mso/msl, the prefix lies at an offset */
prefix += cur->scb_s.mso;
- if (prefix <= end && start <= prefix + PAGE_SIZE - 1)
+ if (prefix <= end && start <= prefix + 2 * PAGE_SIZE - 1)
prefix_unmapped_sync(cur);
}
}
/*
- * Map the first prefix page.
+ * Map the first prefix page and if tx is enabled also the second prefix page.
*
* The prefix will be protected, a gmap notifier will inform about unmaps.
* The shadow scb must not be executed until the prefix is remapped, this is
@@ -370,6 +378,9 @@ static int map_prefix(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
prefix += scb_s->mso;
rc = kvm_s390_shadow_fault(vcpu, vsie_page->gmap, prefix);
+ if (!rc && (scb_s->ecb & 0x10U))
+ rc = kvm_s390_shadow_fault(vcpu, vsie_page->gmap,
+ prefix + PAGE_SIZE);
/*
* We don't have to mprotect, we will be called for all unshadows.
* SIE will detect if protection applies and trigger a validity.
@@ -434,6 +445,13 @@ static void unpin_blocks(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
scb_s->scaol = 0;
scb_s->scaoh = 0;
}
+
+ hpa = scb_s->itdba;
+ if (hpa) {
+ gpa = scb_o->itdba & ~0xffUL;
+ unpin_guest_page(vcpu->kvm, gpa, hpa);
+ scb_s->itdba = 0;
+ }
}
/*
@@ -477,6 +495,21 @@ static int pin_blocks(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
scb_s->scaoh = (u32)((u64)hpa >> 32);
scb_s->scaol = (u32)(u64)hpa;
}
+
+ gpa = scb_o->itdba & ~0xffUL;
+ if (gpa && (scb_s->ecb & 0x10U)) {
+ if (!(gpa & ~0x1fffU)) {
+ rc = set_validity_icpt(scb_s, 0x0080U);
+ goto unpin;
+ }
+ /* 256 bytes cannot cross page boundaries */
+ rc = pin_guest_page(vcpu->kvm, gpa, &hpa);
+ if (rc == -EINVAL)
+ rc = set_validity_icpt(scb_s, 0x0080U);
+ if (rc)
+ goto unpin;
+ scb_s->itdba = hpa;
+ }
return 0;
unpin:
unpin_blocks(vcpu, vsie_page);
--
2.5.5
^ permalink raw reply related [flat|nested] 53+ messages in thread* [GIT PULL 36/51] KVM: s390: vsie: support vectory facility (SIMD)
2016-06-21 13:12 [GIT PULL 00/51] KVM: s390: vSIE (nested virtualization) feature for 4.8 (kvm/next) Christian Borntraeger
` (34 preceding siblings ...)
2016-06-21 13:13 ` [GIT PULL 35/51] KVM: s390: vsie: support transactional execution Christian Borntraeger
@ 2016-06-21 13:13 ` Christian Borntraeger
2016-06-21 13:13 ` [GIT PULL 37/51] KVM: s390: vsie: support run-time-instrumentation Christian Borntraeger
` (15 subsequent siblings)
51 siblings, 0 replies; 53+ messages in thread
From: Christian Borntraeger @ 2016-06-21 13:13 UTC (permalink / raw)
To: Paolo Bonzini, Radim Krčmář
Cc: KVM, Cornelia Huck, linux-s390, Christian Borntraeger,
David Hildenbrand, Martin Schwidefsky
From: David Hildenbrand <dahi@linux.vnet.ibm.com>
As soon as guest 2 is allowed to use the vector facility (indicated via
STFLE), it can also enable it for guest 3. We have to take care of the
sattellite block that might be used when not relying on lazy vector
copying (not the case for KVM).
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
arch/s390/include/asm/kvm_host.h | 2 +-
arch/s390/kvm/vsie.c | 31 +++++++++++++++++++++++++++++++
2 files changed, 32 insertions(+), 1 deletion(-)
diff --git a/arch/s390/include/asm/kvm_host.h b/arch/s390/include/asm/kvm_host.h
index 255609c..190ad63 100644
--- a/arch/s390/include/asm/kvm_host.h
+++ b/arch/s390/include/asm/kvm_host.h
@@ -229,7 +229,7 @@ struct kvm_s390_sie_block {
__u8 reserved1e6[2]; /* 0x01e6 */
__u64 itdba; /* 0x01e8 */
__u64 riccbd; /* 0x01f0 */
- __u8 reserved1f8[8]; /* 0x01f8 */
+ __u64 gvrd; /* 0x01f8 */
} __attribute__((packed));
struct kvm_s390_itdb {
diff --git a/arch/s390/kvm/vsie.c b/arch/s390/kvm/vsie.c
index 4e2c71c..6d9f405 100644
--- a/arch/s390/kvm/vsie.c
+++ b/arch/s390/kvm/vsie.c
@@ -307,6 +307,11 @@ static int shadow_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
prefix_unmapped(vsie_page);
scb_s->ecb |= scb_o->ecb & 0x10U;
}
+ /* SIMD */
+ if (test_kvm_facility(vcpu->kvm, 129)) {
+ scb_s->eca |= scb_o->eca & 0x00020000U;
+ scb_s->ecd |= scb_o->ecd & 0x20000000U;
+ }
prepare_ibc(vcpu, vsie_page);
rc = shadow_crycb(vcpu, vsie_page);
@@ -452,6 +457,13 @@ static void unpin_blocks(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
unpin_guest_page(vcpu->kvm, gpa, hpa);
scb_s->itdba = 0;
}
+
+ hpa = scb_s->gvrd;
+ if (hpa) {
+ gpa = scb_o->gvrd & ~0x1ffUL;
+ unpin_guest_page(vcpu->kvm, gpa, hpa);
+ scb_s->gvrd = 0;
+ }
}
/*
@@ -510,6 +522,25 @@ static int pin_blocks(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
goto unpin;
scb_s->itdba = hpa;
}
+
+ gpa = scb_o->gvrd & ~0x1ffUL;
+ if (gpa && (scb_s->eca & 0x00020000U) &&
+ !(scb_s->ecd & 0x20000000U)) {
+ if (!(gpa & ~0x1fffUL)) {
+ rc = set_validity_icpt(scb_s, 0x1310U);
+ goto unpin;
+ }
+ /*
+ * 512 bytes vector registers cannot cross page boundaries
+ * if this block gets bigger, we have to shadow it.
+ */
+ rc = pin_guest_page(vcpu->kvm, gpa, &hpa);
+ if (rc == -EINVAL)
+ rc = set_validity_icpt(scb_s, 0x1310U);
+ if (rc)
+ goto unpin;
+ scb_s->gvrd = hpa;
+ }
return 0;
unpin:
unpin_blocks(vcpu, vsie_page);
--
2.5.5
^ permalink raw reply related [flat|nested] 53+ messages in thread* [GIT PULL 37/51] KVM: s390: vsie: support run-time-instrumentation
2016-06-21 13:12 [GIT PULL 00/51] KVM: s390: vSIE (nested virtualization) feature for 4.8 (kvm/next) Christian Borntraeger
` (35 preceding siblings ...)
2016-06-21 13:13 ` [GIT PULL 36/51] KVM: s390: vsie: support vectory facility (SIMD) Christian Borntraeger
@ 2016-06-21 13:13 ` Christian Borntraeger
2016-06-21 13:13 ` [GIT PULL 38/51] KVM: s390: vsie: support 64-bit-SCAO Christian Borntraeger
` (14 subsequent siblings)
51 siblings, 0 replies; 53+ messages in thread
From: Christian Borntraeger @ 2016-06-21 13:13 UTC (permalink / raw)
To: Paolo Bonzini, Radim Krčmář
Cc: KVM, Cornelia Huck, linux-s390, Christian Borntraeger,
David Hildenbrand, Martin Schwidefsky
From: David Hildenbrand <dahi@linux.vnet.ibm.com>
As soon as guest 2 is allowed to use run-time-instrumentation (indicated
via via STFLE), it can also enable it for guest 3.
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
arch/s390/kvm/vsie.c | 26 ++++++++++++++++++++++++++
1 file changed, 26 insertions(+)
diff --git a/arch/s390/kvm/vsie.c b/arch/s390/kvm/vsie.c
index 6d9f405..ebc988f 100644
--- a/arch/s390/kvm/vsie.c
+++ b/arch/s390/kvm/vsie.c
@@ -312,6 +312,9 @@ static int shadow_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
scb_s->eca |= scb_o->eca & 0x00020000U;
scb_s->ecd |= scb_o->ecd & 0x20000000U;
}
+ /* Run-time-Instrumentation */
+ if (test_kvm_facility(vcpu->kvm, 64))
+ scb_s->ecb3 |= scb_o->ecb3 & 0x01U;
prepare_ibc(vcpu, vsie_page);
rc = shadow_crycb(vcpu, vsie_page);
@@ -464,6 +467,13 @@ static void unpin_blocks(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
unpin_guest_page(vcpu->kvm, gpa, hpa);
scb_s->gvrd = 0;
}
+
+ hpa = scb_s->riccbd;
+ if (hpa) {
+ gpa = scb_o->riccbd & ~0x3fUL;
+ unpin_guest_page(vcpu->kvm, gpa, hpa);
+ scb_s->riccbd = 0;
+ }
}
/*
@@ -541,6 +551,22 @@ static int pin_blocks(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
goto unpin;
scb_s->gvrd = hpa;
}
+
+ gpa = scb_o->riccbd & ~0x3fUL;
+ if (gpa && (scb_s->ecb3 & 0x01U)) {
+ if (!(gpa & ~0x1fffUL)) {
+ rc = set_validity_icpt(scb_s, 0x0043U);
+ goto unpin;
+ }
+ /* 64 bytes cannot cross page boundaries */
+ rc = pin_guest_page(vcpu->kvm, gpa, &hpa);
+ if (rc == -EINVAL)
+ rc = set_validity_icpt(scb_s, 0x0043U);
+ /* Validity 0x0044 will be checked by SIE */
+ if (rc)
+ goto unpin;
+ scb_s->gvrd = hpa;
+ }
return 0;
unpin:
unpin_blocks(vcpu, vsie_page);
--
2.5.5
^ permalink raw reply related [flat|nested] 53+ messages in thread* [GIT PULL 38/51] KVM: s390: vsie: support 64-bit-SCAO
2016-06-21 13:12 [GIT PULL 00/51] KVM: s390: vSIE (nested virtualization) feature for 4.8 (kvm/next) Christian Borntraeger
` (36 preceding siblings ...)
2016-06-21 13:13 ` [GIT PULL 37/51] KVM: s390: vsie: support run-time-instrumentation Christian Borntraeger
@ 2016-06-21 13:13 ` Christian Borntraeger
2016-06-21 13:13 ` [GIT PULL 39/51] KVM: s390: vsie: support shared IPTE-interlock facility Christian Borntraeger
` (13 subsequent siblings)
51 siblings, 0 replies; 53+ messages in thread
From: Christian Borntraeger @ 2016-06-21 13:13 UTC (permalink / raw)
To: Paolo Bonzini, Radim Krčmář
Cc: KVM, Cornelia Huck, linux-s390, Christian Borntraeger,
David Hildenbrand, Martin Schwidefsky
From: David Hildenbrand <dahi@linux.vnet.ibm.com>
Let's provide the 64-bit-SCAO facility to guest 2, so he can set up a SCA
for guest 3 that has a 64 bit address. Please note that we already require
the 64 bit SCAO for our vsie implementation, in order to forward the SCA
directly (by pinning the page).
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
arch/s390/include/uapi/asm/kvm.h | 1 +
arch/s390/kvm/kvm-s390.c | 2 ++
arch/s390/kvm/vsie.c | 4 ++++
3 files changed, 7 insertions(+)
diff --git a/arch/s390/include/uapi/asm/kvm.h b/arch/s390/include/uapi/asm/kvm.h
index 62423b1..c5e4537 100644
--- a/arch/s390/include/uapi/asm/kvm.h
+++ b/arch/s390/include/uapi/asm/kvm.h
@@ -99,6 +99,7 @@ struct kvm_s390_vm_cpu_machine {
#define KVM_S390_VM_CPU_FEAT_NR_BITS 1024
#define KVM_S390_VM_CPU_FEAT_ESOP 0
#define KVM_S390_VM_CPU_FEAT_SIEF2 1
+#define KVM_S390_VM_CPU_FEAT_64BSCAO 2
struct kvm_s390_vm_cpu_feat {
__u64 feat[16];
};
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 3fb1242..e0c5a57 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -265,6 +265,8 @@ static void kvm_s390_cpu_feat_init(void)
!test_facility(3))
return;
allow_cpu_feat(KVM_S390_VM_CPU_FEAT_SIEF2);
+ if (sclp.has_64bscao)
+ allow_cpu_feat(KVM_S390_VM_CPU_FEAT_64BSCAO);
}
int kvm_arch_init(void *opaque)
diff --git a/arch/s390/kvm/vsie.c b/arch/s390/kvm/vsie.c
index ebc988f..44e66c3 100644
--- a/arch/s390/kvm/vsie.c
+++ b/arch/s390/kvm/vsie.c
@@ -449,6 +449,8 @@ static void unpin_blocks(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
hpa = (u64) scb_s->scaoh << 32 | scb_s->scaol;
if (hpa) {
gpa = scb_o->scaol & ~0xfUL;
+ if (test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_64BSCAO))
+ gpa |= (u64) scb_o->scaoh << 32;
unpin_guest_page(vcpu->kvm, gpa, hpa);
scb_s->scaol = 0;
scb_s->scaoh = 0;
@@ -499,6 +501,8 @@ static int pin_blocks(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
int rc = 0;
gpa = scb_o->scaol & ~0xfUL;
+ if (test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_64BSCAO))
+ gpa |= (u64) scb_o->scaoh << 32;
if (gpa) {
if (!(gpa & ~0x1fffUL))
rc = set_validity_icpt(scb_s, 0x0038U);
--
2.5.5
^ permalink raw reply related [flat|nested] 53+ messages in thread* [GIT PULL 39/51] KVM: s390: vsie: support shared IPTE-interlock facility
2016-06-21 13:12 [GIT PULL 00/51] KVM: s390: vSIE (nested virtualization) feature for 4.8 (kvm/next) Christian Borntraeger
` (37 preceding siblings ...)
2016-06-21 13:13 ` [GIT PULL 38/51] KVM: s390: vsie: support 64-bit-SCAO Christian Borntraeger
@ 2016-06-21 13:13 ` Christian Borntraeger
2016-06-21 13:13 ` [GIT PULL 40/51] KVM: s390: vsie: support guest-PER-enhancement Christian Borntraeger
` (12 subsequent siblings)
51 siblings, 0 replies; 53+ messages in thread
From: Christian Borntraeger @ 2016-06-21 13:13 UTC (permalink / raw)
To: Paolo Bonzini, Radim Krčmář
Cc: KVM, Cornelia Huck, linux-s390, Christian Borntraeger,
David Hildenbrand, Martin Schwidefsky
From: David Hildenbrand <dahi@linux.vnet.ibm.com>
As we forward the whole SCA provided by guest 2, we can directly forward
SIIF if available.
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
arch/s390/include/uapi/asm/kvm.h | 1 +
arch/s390/kvm/kvm-s390.c | 2 ++
arch/s390/kvm/vsie.c | 2 ++
3 files changed, 5 insertions(+)
diff --git a/arch/s390/include/uapi/asm/kvm.h b/arch/s390/include/uapi/asm/kvm.h
index c5e4537..1d2e820 100644
--- a/arch/s390/include/uapi/asm/kvm.h
+++ b/arch/s390/include/uapi/asm/kvm.h
@@ -100,6 +100,7 @@ struct kvm_s390_vm_cpu_machine {
#define KVM_S390_VM_CPU_FEAT_ESOP 0
#define KVM_S390_VM_CPU_FEAT_SIEF2 1
#define KVM_S390_VM_CPU_FEAT_64BSCAO 2
+#define KVM_S390_VM_CPU_FEAT_SIIF 3
struct kvm_s390_vm_cpu_feat {
__u64 feat[16];
};
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index e0c5a57..d735612 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -267,6 +267,8 @@ static void kvm_s390_cpu_feat_init(void)
allow_cpu_feat(KVM_S390_VM_CPU_FEAT_SIEF2);
if (sclp.has_64bscao)
allow_cpu_feat(KVM_S390_VM_CPU_FEAT_64BSCAO);
+ if (sclp.has_siif)
+ allow_cpu_feat(KVM_S390_VM_CPU_FEAT_SIIF);
}
int kvm_arch_init(void *opaque)
diff --git a/arch/s390/kvm/vsie.c b/arch/s390/kvm/vsie.c
index 44e66c3..1615ed3 100644
--- a/arch/s390/kvm/vsie.c
+++ b/arch/s390/kvm/vsie.c
@@ -315,6 +315,8 @@ static int shadow_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
/* Run-time-Instrumentation */
if (test_kvm_facility(vcpu->kvm, 64))
scb_s->ecb3 |= scb_o->ecb3 & 0x01U;
+ if (test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_SIIF))
+ scb_s->eca |= scb_o->eca & 0x00000001U;
prepare_ibc(vcpu, vsie_page);
rc = shadow_crycb(vcpu, vsie_page);
--
2.5.5
^ permalink raw reply related [flat|nested] 53+ messages in thread* [GIT PULL 40/51] KVM: s390: vsie: support guest-PER-enhancement
2016-06-21 13:12 [GIT PULL 00/51] KVM: s390: vSIE (nested virtualization) feature for 4.8 (kvm/next) Christian Borntraeger
` (38 preceding siblings ...)
2016-06-21 13:13 ` [GIT PULL 39/51] KVM: s390: vsie: support shared IPTE-interlock facility Christian Borntraeger
@ 2016-06-21 13:13 ` Christian Borntraeger
2016-06-21 13:13 ` [GIT PULL 41/51] KVM: s390: vsie: support guest-storage-limit-suppression Christian Borntraeger
` (11 subsequent siblings)
51 siblings, 0 replies; 53+ messages in thread
From: Christian Borntraeger @ 2016-06-21 13:13 UTC (permalink / raw)
To: Paolo Bonzini, Radim Krčmář
Cc: KVM, Cornelia Huck, linux-s390, Christian Borntraeger,
David Hildenbrand, Martin Schwidefsky
From: David Hildenbrand <dahi@linux.vnet.ibm.com>
We can easily forward the guest-PER-enhancement facility to guest 2 if
available.
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
arch/s390/include/uapi/asm/kvm.h | 1 +
arch/s390/kvm/kvm-s390.c | 2 ++
arch/s390/kvm/vsie.c | 2 ++
3 files changed, 5 insertions(+)
diff --git a/arch/s390/include/uapi/asm/kvm.h b/arch/s390/include/uapi/asm/kvm.h
index 1d2e820..98526ac 100644
--- a/arch/s390/include/uapi/asm/kvm.h
+++ b/arch/s390/include/uapi/asm/kvm.h
@@ -101,6 +101,7 @@ struct kvm_s390_vm_cpu_machine {
#define KVM_S390_VM_CPU_FEAT_SIEF2 1
#define KVM_S390_VM_CPU_FEAT_64BSCAO 2
#define KVM_S390_VM_CPU_FEAT_SIIF 3
+#define KVM_S390_VM_CPU_FEAT_GPERE 4
struct kvm_s390_vm_cpu_feat {
__u64 feat[16];
};
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index d735612..1757528 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -269,6 +269,8 @@ static void kvm_s390_cpu_feat_init(void)
allow_cpu_feat(KVM_S390_VM_CPU_FEAT_64BSCAO);
if (sclp.has_siif)
allow_cpu_feat(KVM_S390_VM_CPU_FEAT_SIIF);
+ if (sclp.has_gpere)
+ allow_cpu_feat(KVM_S390_VM_CPU_FEAT_GPERE);
}
int kvm_arch_init(void *opaque)
diff --git a/arch/s390/kvm/vsie.c b/arch/s390/kvm/vsie.c
index 1615ed3..b8792ef 100644
--- a/arch/s390/kvm/vsie.c
+++ b/arch/s390/kvm/vsie.c
@@ -107,6 +107,8 @@ static int prepare_cpuflags(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
return set_validity_icpt(scb_s, 0x0001U);
newflags |= CPUSTAT_GED2;
}
+ if (test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_GPERE))
+ newflags |= cpuflags & CPUSTAT_P;
atomic_set(&scb_s->cpuflags, newflags);
return 0;
--
2.5.5
^ permalink raw reply related [flat|nested] 53+ messages in thread* [GIT PULL 41/51] KVM: s390: vsie: support guest-storage-limit-suppression
2016-06-21 13:12 [GIT PULL 00/51] KVM: s390: vSIE (nested virtualization) feature for 4.8 (kvm/next) Christian Borntraeger
` (39 preceding siblings ...)
2016-06-21 13:13 ` [GIT PULL 40/51] KVM: s390: vsie: support guest-PER-enhancement Christian Borntraeger
@ 2016-06-21 13:13 ` Christian Borntraeger
2016-06-21 13:13 ` [GIT PULL 42/51] KVM: s390: vsie: support intervention-bypass Christian Borntraeger
` (10 subsequent siblings)
51 siblings, 0 replies; 53+ messages in thread
From: Christian Borntraeger @ 2016-06-21 13:13 UTC (permalink / raw)
To: Paolo Bonzini, Radim Krčmář
Cc: KVM, Cornelia Huck, linux-s390, Christian Borntraeger,
David Hildenbrand, Martin Schwidefsky
From: David Hildenbrand <dahi@linux.vnet.ibm.com>
We can easily forward guest-storage-limit-suppression if available.
One thing to care about is keeping the prefix properly mapped when
gsls in toggled on/off or the mso changes in between. Therefore we better
remap the prefix on any mso changes just like we already do with the
prefix.
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
arch/s390/include/uapi/asm/kvm.h | 1 +
arch/s390/kvm/kvm-s390.c | 2 ++
arch/s390/kvm/vsie.c | 7 +++++--
3 files changed, 8 insertions(+), 2 deletions(-)
diff --git a/arch/s390/include/uapi/asm/kvm.h b/arch/s390/include/uapi/asm/kvm.h
index 98526ac..9ed0747 100644
--- a/arch/s390/include/uapi/asm/kvm.h
+++ b/arch/s390/include/uapi/asm/kvm.h
@@ -102,6 +102,7 @@ struct kvm_s390_vm_cpu_machine {
#define KVM_S390_VM_CPU_FEAT_64BSCAO 2
#define KVM_S390_VM_CPU_FEAT_SIIF 3
#define KVM_S390_VM_CPU_FEAT_GPERE 4
+#define KVM_S390_VM_CPU_FEAT_GSLS 5
struct kvm_s390_vm_cpu_feat {
__u64 feat[16];
};
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 1757528..ce9813a 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -271,6 +271,8 @@ static void kvm_s390_cpu_feat_init(void)
allow_cpu_feat(KVM_S390_VM_CPU_FEAT_SIIF);
if (sclp.has_gpere)
allow_cpu_feat(KVM_S390_VM_CPU_FEAT_GPERE);
+ if (sclp.has_gsls)
+ allow_cpu_feat(KVM_S390_VM_CPU_FEAT_GSLS);
}
int kvm_arch_init(void *opaque)
diff --git a/arch/s390/kvm/vsie.c b/arch/s390/kvm/vsie.c
index b8792ef..ea65bf2 100644
--- a/arch/s390/kvm/vsie.c
+++ b/arch/s390/kvm/vsie.c
@@ -109,6 +109,8 @@ static int prepare_cpuflags(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
}
if (test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_GPERE))
newflags |= cpuflags & CPUSTAT_P;
+ if (test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_GSLS))
+ newflags |= cpuflags & CPUSTAT_SM;
atomic_set(&scb_s->cpuflags, newflags);
return 0;
@@ -242,7 +244,7 @@ static int shadow_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
struct kvm_s390_sie_block *scb_o = vsie_page->scb_o;
struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s;
bool had_tx = scb_s->ecb & 0x10U;
- unsigned long new_mso;
+ unsigned long new_mso = 0;
int rc;
/* make sure we don't have any leftovers when reusing the scb */
@@ -284,7 +286,8 @@ static int shadow_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
scb_s->ictl |= ICTL_ISKE | ICTL_SSKE | ICTL_RRBE;
scb_s->icpua = scb_o->icpua;
- new_mso = scb_o->mso & 0xfffffffffff00000UL;
+ if (!(atomic_read(&scb_s->cpuflags) & CPUSTAT_SM))
+ new_mso = scb_o->mso & 0xfffffffffff00000UL;
/* if the hva of the prefix changes, we have to remap the prefix */
if (scb_s->mso != new_mso || scb_s->prefix != scb_o->prefix)
prefix_unmapped(vsie_page);
--
2.5.5
^ permalink raw reply related [flat|nested] 53+ messages in thread* [GIT PULL 42/51] KVM: s390: vsie: support intervention-bypass
2016-06-21 13:12 [GIT PULL 00/51] KVM: s390: vSIE (nested virtualization) feature for 4.8 (kvm/next) Christian Borntraeger
` (40 preceding siblings ...)
2016-06-21 13:13 ` [GIT PULL 41/51] KVM: s390: vsie: support guest-storage-limit-suppression Christian Borntraeger
@ 2016-06-21 13:13 ` Christian Borntraeger
2016-06-21 13:13 ` [GIT PULL 43/51] KVM: s390: vsie: support conditional-external-interception Christian Borntraeger
` (9 subsequent siblings)
51 siblings, 0 replies; 53+ messages in thread
From: Christian Borntraeger @ 2016-06-21 13:13 UTC (permalink / raw)
To: Paolo Bonzini, Radim Krčmář
Cc: KVM, Cornelia Huck, linux-s390, Christian Borntraeger,
David Hildenbrand, Martin Schwidefsky
From: David Hildenbrand <dahi@linux.vnet.ibm.com>
We can easily enable intervention bypass for guest 2, so it can use it
for guest 3.
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
arch/s390/include/uapi/asm/kvm.h | 1 +
arch/s390/kvm/kvm-s390.c | 2 ++
arch/s390/kvm/vsie.c | 2 ++
3 files changed, 5 insertions(+)
diff --git a/arch/s390/include/uapi/asm/kvm.h b/arch/s390/include/uapi/asm/kvm.h
index 9ed0747..347f4f6 100644
--- a/arch/s390/include/uapi/asm/kvm.h
+++ b/arch/s390/include/uapi/asm/kvm.h
@@ -103,6 +103,7 @@ struct kvm_s390_vm_cpu_machine {
#define KVM_S390_VM_CPU_FEAT_SIIF 3
#define KVM_S390_VM_CPU_FEAT_GPERE 4
#define KVM_S390_VM_CPU_FEAT_GSLS 5
+#define KVM_S390_VM_CPU_FEAT_IB 6
struct kvm_s390_vm_cpu_feat {
__u64 feat[16];
};
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index ce9813a..5ec598c 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -273,6 +273,8 @@ static void kvm_s390_cpu_feat_init(void)
allow_cpu_feat(KVM_S390_VM_CPU_FEAT_GPERE);
if (sclp.has_gsls)
allow_cpu_feat(KVM_S390_VM_CPU_FEAT_GSLS);
+ if (sclp.has_ib)
+ allow_cpu_feat(KVM_S390_VM_CPU_FEAT_IB);
}
int kvm_arch_init(void *opaque)
diff --git a/arch/s390/kvm/vsie.c b/arch/s390/kvm/vsie.c
index ea65bf2..d29bd59 100644
--- a/arch/s390/kvm/vsie.c
+++ b/arch/s390/kvm/vsie.c
@@ -322,6 +322,8 @@ static int shadow_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
scb_s->ecb3 |= scb_o->ecb3 & 0x01U;
if (test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_SIIF))
scb_s->eca |= scb_o->eca & 0x00000001U;
+ if (test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_IB))
+ scb_s->eca |= scb_o->eca & 0x40000000U;
prepare_ibc(vcpu, vsie_page);
rc = shadow_crycb(vcpu, vsie_page);
--
2.5.5
^ permalink raw reply related [flat|nested] 53+ messages in thread* [GIT PULL 43/51] KVM: s390: vsie: support conditional-external-interception
2016-06-21 13:12 [GIT PULL 00/51] KVM: s390: vSIE (nested virtualization) feature for 4.8 (kvm/next) Christian Borntraeger
` (41 preceding siblings ...)
2016-06-21 13:13 ` [GIT PULL 42/51] KVM: s390: vsie: support intervention-bypass Christian Borntraeger
@ 2016-06-21 13:13 ` Christian Borntraeger
2016-06-21 13:13 ` [GIT PULL 44/51] KVM: s390: vsie: support IBS interpretation Christian Borntraeger
` (8 subsequent siblings)
51 siblings, 0 replies; 53+ messages in thread
From: Christian Borntraeger @ 2016-06-21 13:13 UTC (permalink / raw)
To: Paolo Bonzini, Radim Krčmář
Cc: KVM, Cornelia Huck, linux-s390, Christian Borntraeger,
David Hildenbrand, Martin Schwidefsky
From: David Hildenbrand <dahi@linux.vnet.ibm.com>
We can easily enable cei for guest 2, so he can use it for guest 3.
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
arch/s390/include/uapi/asm/kvm.h | 1 +
arch/s390/kvm/kvm-s390.c | 2 ++
arch/s390/kvm/vsie.c | 2 ++
3 files changed, 5 insertions(+)
diff --git a/arch/s390/include/uapi/asm/kvm.h b/arch/s390/include/uapi/asm/kvm.h
index 347f4f6..7630dd7 100644
--- a/arch/s390/include/uapi/asm/kvm.h
+++ b/arch/s390/include/uapi/asm/kvm.h
@@ -104,6 +104,7 @@ struct kvm_s390_vm_cpu_machine {
#define KVM_S390_VM_CPU_FEAT_GPERE 4
#define KVM_S390_VM_CPU_FEAT_GSLS 5
#define KVM_S390_VM_CPU_FEAT_IB 6
+#define KVM_S390_VM_CPU_FEAT_CEI 7
struct kvm_s390_vm_cpu_feat {
__u64 feat[16];
};
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 5ec598c..1c1188b 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -275,6 +275,8 @@ static void kvm_s390_cpu_feat_init(void)
allow_cpu_feat(KVM_S390_VM_CPU_FEAT_GSLS);
if (sclp.has_ib)
allow_cpu_feat(KVM_S390_VM_CPU_FEAT_IB);
+ if (sclp.has_cei)
+ allow_cpu_feat(KVM_S390_VM_CPU_FEAT_CEI);
}
int kvm_arch_init(void *opaque)
diff --git a/arch/s390/kvm/vsie.c b/arch/s390/kvm/vsie.c
index d29bd59..f3a4a0b 100644
--- a/arch/s390/kvm/vsie.c
+++ b/arch/s390/kvm/vsie.c
@@ -324,6 +324,8 @@ static int shadow_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
scb_s->eca |= scb_o->eca & 0x00000001U;
if (test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_IB))
scb_s->eca |= scb_o->eca & 0x40000000U;
+ if (test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_CEI))
+ scb_s->eca |= scb_o->eca & 0x80000000U;
prepare_ibc(vcpu, vsie_page);
rc = shadow_crycb(vcpu, vsie_page);
--
2.5.5
^ permalink raw reply related [flat|nested] 53+ messages in thread* [GIT PULL 44/51] KVM: s390: vsie: support IBS interpretation
2016-06-21 13:12 [GIT PULL 00/51] KVM: s390: vSIE (nested virtualization) feature for 4.8 (kvm/next) Christian Borntraeger
` (42 preceding siblings ...)
2016-06-21 13:13 ` [GIT PULL 43/51] KVM: s390: vsie: support conditional-external-interception Christian Borntraeger
@ 2016-06-21 13:13 ` Christian Borntraeger
2016-06-21 13:13 ` [GIT PULL 45/51] KVM: s390: vsie: try to refault after a reported fault to g2 Christian Borntraeger
` (7 subsequent siblings)
51 siblings, 0 replies; 53+ messages in thread
From: Christian Borntraeger @ 2016-06-21 13:13 UTC (permalink / raw)
To: Paolo Bonzini, Radim Krčmář
Cc: KVM, Cornelia Huck, linux-s390, Christian Borntraeger,
David Hildenbrand, Martin Schwidefsky
From: David Hildenbrand <dahi@linux.vnet.ibm.com>
We can easily enable ibs for guest 2, so he can use it for guest 3.
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
arch/s390/include/uapi/asm/kvm.h | 1 +
arch/s390/kvm/kvm-s390.c | 2 ++
arch/s390/kvm/vsie.c | 2 ++
3 files changed, 5 insertions(+)
diff --git a/arch/s390/include/uapi/asm/kvm.h b/arch/s390/include/uapi/asm/kvm.h
index 7630dd7..c128567 100644
--- a/arch/s390/include/uapi/asm/kvm.h
+++ b/arch/s390/include/uapi/asm/kvm.h
@@ -105,6 +105,7 @@ struct kvm_s390_vm_cpu_machine {
#define KVM_S390_VM_CPU_FEAT_GSLS 5
#define KVM_S390_VM_CPU_FEAT_IB 6
#define KVM_S390_VM_CPU_FEAT_CEI 7
+#define KVM_S390_VM_CPU_FEAT_IBS 8
struct kvm_s390_vm_cpu_feat {
__u64 feat[16];
};
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 1c1188b..8ba7a98 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -277,6 +277,8 @@ static void kvm_s390_cpu_feat_init(void)
allow_cpu_feat(KVM_S390_VM_CPU_FEAT_IB);
if (sclp.has_cei)
allow_cpu_feat(KVM_S390_VM_CPU_FEAT_CEI);
+ if (sclp.has_ibs)
+ allow_cpu_feat(KVM_S390_VM_CPU_FEAT_IBS);
}
int kvm_arch_init(void *opaque)
diff --git a/arch/s390/kvm/vsie.c b/arch/s390/kvm/vsie.c
index f3a4a0b..3ececbb 100644
--- a/arch/s390/kvm/vsie.c
+++ b/arch/s390/kvm/vsie.c
@@ -111,6 +111,8 @@ static int prepare_cpuflags(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
newflags |= cpuflags & CPUSTAT_P;
if (test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_GSLS))
newflags |= cpuflags & CPUSTAT_SM;
+ if (test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_IBS))
+ newflags |= cpuflags & CPUSTAT_IBS;
atomic_set(&scb_s->cpuflags, newflags);
return 0;
--
2.5.5
^ permalink raw reply related [flat|nested] 53+ messages in thread* [GIT PULL 45/51] KVM: s390: vsie: try to refault after a reported fault to g2
2016-06-21 13:12 [GIT PULL 00/51] KVM: s390: vSIE (nested virtualization) feature for 4.8 (kvm/next) Christian Borntraeger
` (43 preceding siblings ...)
2016-06-21 13:13 ` [GIT PULL 44/51] KVM: s390: vsie: support IBS interpretation Christian Borntraeger
@ 2016-06-21 13:13 ` Christian Borntraeger
2016-06-21 13:13 ` [GIT PULL 46/51] KVM: s390: vsie: speed up VCPU irq delivery when handling vsie Christian Borntraeger
` (6 subsequent siblings)
51 siblings, 0 replies; 53+ messages in thread
From: Christian Borntraeger @ 2016-06-21 13:13 UTC (permalink / raw)
To: Paolo Bonzini, Radim Krčmář
Cc: KVM, Cornelia Huck, linux-s390, Christian Borntraeger,
David Hildenbrand, Martin Schwidefsky
From: David Hildenbrand <dahi@linux.vnet.ibm.com>
We can avoid one unneeded SIE entry after we reported a fault to g2.
Theoretically, g2 resolves the fault and we can create the shadow mapping
directly, instead of failing again when entering the SIE.
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
arch/s390/kvm/vsie.c | 24 +++++++++++++++++++++++-
1 file changed, 23 insertions(+), 1 deletion(-)
diff --git a/arch/s390/kvm/vsie.c b/arch/s390/kvm/vsie.c
index 3ececbb..7482488 100644
--- a/arch/s390/kvm/vsie.c
+++ b/arch/s390/kvm/vsie.c
@@ -28,7 +28,9 @@ struct vsie_page {
struct kvm_s390_sie_block *scb_o; /* 0x0200 */
/* the shadow gmap in use by the vsie_page */
struct gmap *gmap; /* 0x0208 */
- __u8 reserved[0x0700 - 0x0210]; /* 0x0210 */
+ /* address of the last reported fault to guest2 */
+ unsigned long fault_addr; /* 0x0210 */
+ __u8 reserved[0x0700 - 0x0218]; /* 0x0218 */
struct kvm_s390_crypto_cb crycb; /* 0x0700 */
__u8 fac[S390_ARCH_FAC_LIST_SIZE_BYTE]; /* 0x0800 */
} __packed;
@@ -676,10 +678,27 @@ static int handle_fault(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
rc = inject_fault(vcpu, rc,
current->thread.gmap_addr,
current->thread.gmap_write_flag);
+ if (rc >= 0)
+ vsie_page->fault_addr = current->thread.gmap_addr;
}
return rc;
}
+/*
+ * Retry the previous fault that required guest 2 intervention. This avoids
+ * one superfluous SIE re-entry and direct exit.
+ *
+ * Will ignore any errors. The next SIE fault will do proper fault handling.
+ */
+static void handle_last_fault(struct kvm_vcpu *vcpu,
+ struct vsie_page *vsie_page)
+{
+ if (vsie_page->fault_addr)
+ kvm_s390_shadow_fault(vcpu, vsie_page->gmap,
+ vsie_page->fault_addr);
+ vsie_page->fault_addr = 0;
+}
+
static inline void clear_vsie_icpt(struct vsie_page *vsie_page)
{
vsie_page->scb_s.icptcode = 0;
@@ -737,6 +756,8 @@ static int do_vsie_run(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
struct kvm_s390_sie_block *scb_o = vsie_page->scb_o;
int rc;
+ handle_last_fault(vcpu, vsie_page);
+
if (need_resched())
schedule();
if (test_cpu_flag(CIF_MCCK_PENDING))
@@ -928,6 +949,7 @@ static struct vsie_page *get_vsie_page(struct kvm *kvm, unsigned long addr)
vsie_page = page_to_virt(page);
memset(&vsie_page->scb_s, 0, sizeof(struct kvm_s390_sie_block));
release_gmap_shadow(vsie_page);
+ vsie_page->fault_addr = 0;
vsie_page->scb_s.ihcpu = 0xffffU;
return vsie_page;
}
--
2.5.5
^ permalink raw reply related [flat|nested] 53+ messages in thread* [GIT PULL 46/51] KVM: s390: vsie: speed up VCPU irq delivery when handling vsie
2016-06-21 13:12 [GIT PULL 00/51] KVM: s390: vSIE (nested virtualization) feature for 4.8 (kvm/next) Christian Borntraeger
` (44 preceding siblings ...)
2016-06-21 13:13 ` [GIT PULL 45/51] KVM: s390: vsie: try to refault after a reported fault to g2 Christian Borntraeger
@ 2016-06-21 13:13 ` Christian Borntraeger
2016-06-21 13:13 ` [GIT PULL 47/51] KVM: s390: don't use CPUSTAT_WAIT to detect if a VCPU is idle Christian Borntraeger
` (5 subsequent siblings)
51 siblings, 0 replies; 53+ messages in thread
From: Christian Borntraeger @ 2016-06-21 13:13 UTC (permalink / raw)
To: Paolo Bonzini, Radim Krčmář
Cc: KVM, Cornelia Huck, linux-s390, Christian Borntraeger,
David Hildenbrand, Martin Schwidefsky
From: David Hildenbrand <dahi@linux.vnet.ibm.com>
Whenever we want to wake up a VCPU (e.g. when injecting an IRQ), we
have to kick it out of vsie, so the request will be handled faster.
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
arch/s390/include/asm/kvm_host.h | 2 ++
arch/s390/kvm/interrupt.c | 5 +++++
arch/s390/kvm/kvm-s390.h | 1 +
arch/s390/kvm/vsie.c | 35 +++++++++++++++++++++++++++++++++++
4 files changed, 43 insertions(+)
diff --git a/arch/s390/include/asm/kvm_host.h b/arch/s390/include/asm/kvm_host.h
index 190ad63..946fc86 100644
--- a/arch/s390/include/asm/kvm_host.h
+++ b/arch/s390/include/asm/kvm_host.h
@@ -549,6 +549,8 @@ struct kvm_guestdbg_info_arch {
struct kvm_vcpu_arch {
struct kvm_s390_sie_block *sie_block;
+ /* if vsie is active, currently executed shadow sie control block */
+ struct kvm_s390_sie_block *vsie_block;
unsigned int host_acrs[NUM_ACRS];
struct fpu host_fpregs;
struct kvm_s390_local_interrupt local_int;
diff --git a/arch/s390/kvm/interrupt.c b/arch/s390/kvm/interrupt.c
index d72c4a8..ca19627 100644
--- a/arch/s390/kvm/interrupt.c
+++ b/arch/s390/kvm/interrupt.c
@@ -995,6 +995,11 @@ void kvm_s390_vcpu_wakeup(struct kvm_vcpu *vcpu)
swake_up(&vcpu->wq);
vcpu->stat.halt_wakeup++;
}
+ /*
+ * The VCPU might not be sleeping but is executing the VSIE. Let's
+ * kick it, so it leaves the SIE to process the request.
+ */
+ kvm_s390_vsie_kick(vcpu);
}
enum hrtimer_restart kvm_s390_idle_wakeup(struct hrtimer *timer)
diff --git a/arch/s390/kvm/kvm-s390.h b/arch/s390/kvm/kvm-s390.h
index b137fba..ffbbdd28 100644
--- a/arch/s390/kvm/kvm-s390.h
+++ b/arch/s390/kvm/kvm-s390.h
@@ -254,6 +254,7 @@ int kvm_s390_handle_eb(struct kvm_vcpu *vcpu);
/* implemented in vsie.c */
int kvm_s390_handle_vsie(struct kvm_vcpu *vcpu);
+void kvm_s390_vsie_kick(struct kvm_vcpu *vcpu);
void kvm_s390_vsie_gmap_notifier(struct gmap *gmap, unsigned long start,
unsigned long end);
void kvm_s390_vsie_init(struct kvm *kvm);
diff --git a/arch/s390/kvm/vsie.c b/arch/s390/kvm/vsie.c
index 7482488..c8c8763 100644
--- a/arch/s390/kvm/vsie.c
+++ b/arch/s390/kvm/vsie.c
@@ -838,6 +838,23 @@ static int acquire_gmap_shadow(struct kvm_vcpu *vcpu,
}
/*
+ * Register the shadow scb at the VCPU, e.g. for kicking out of vsie.
+ */
+static void register_shadow_scb(struct kvm_vcpu *vcpu,
+ struct vsie_page *vsie_page)
+{
+ WRITE_ONCE(vcpu->arch.vsie_block, &vsie_page->scb_s);
+}
+
+/*
+ * Unregister a shadow scb from a VCPU.
+ */
+static void unregister_shadow_scb(struct kvm_vcpu *vcpu)
+{
+ WRITE_ONCE(vcpu->arch.vsie_block, NULL);
+}
+
+/*
* Run the vsie on a shadowed scb, managing the gmap shadow, handling
* prefix pages and faults.
*
@@ -860,6 +877,7 @@ static int vsie_run(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
rc = do_vsie_run(vcpu, vsie_page);
gmap_enable(vcpu->arch.gmap);
}
+ atomic_andnot(PROG_BLOCK_SIE, &scb_s->prog20);
if (rc == -EAGAIN)
rc = 0;
@@ -1000,7 +1018,9 @@ int kvm_s390_handle_vsie(struct kvm_vcpu *vcpu)
rc = pin_blocks(vcpu, vsie_page);
if (rc)
goto out_unshadow;
+ register_shadow_scb(vcpu, vsie_page);
rc = vsie_run(vcpu, vsie_page);
+ unregister_shadow_scb(vcpu);
unpin_blocks(vcpu, vsie_page);
out_unshadow:
unshadow_scb(vcpu, vsie_page);
@@ -1039,3 +1059,18 @@ void kvm_s390_vsie_destroy(struct kvm *kvm)
kvm->arch.vsie.page_count = 0;
mutex_unlock(&kvm->arch.vsie.mutex);
}
+
+void kvm_s390_vsie_kick(struct kvm_vcpu *vcpu)
+{
+ struct kvm_s390_sie_block *scb = READ_ONCE(vcpu->arch.vsie_block);
+
+ /*
+ * Even if the VCPU lets go of the shadow sie block reference, it is
+ * still valid in the cache. So we can safely kick it.
+ */
+ if (scb) {
+ atomic_or(PROG_BLOCK_SIE, &scb->prog20);
+ if (scb->prog0c & PROG_IN_SIE)
+ atomic_or(CPUSTAT_STOP_INT, &scb->cpuflags);
+ }
+}
--
2.5.5
^ permalink raw reply related [flat|nested] 53+ messages in thread* [GIT PULL 47/51] KVM: s390: don't use CPUSTAT_WAIT to detect if a VCPU is idle
2016-06-21 13:12 [GIT PULL 00/51] KVM: s390: vSIE (nested virtualization) feature for 4.8 (kvm/next) Christian Borntraeger
` (45 preceding siblings ...)
2016-06-21 13:13 ` [GIT PULL 46/51] KVM: s390: vsie: speed up VCPU irq delivery when handling vsie Christian Borntraeger
@ 2016-06-21 13:13 ` Christian Borntraeger
2016-06-21 13:13 ` [GIT PULL 48/51] KVM: s390: vsie: speed up VCPU external calls Christian Borntraeger
` (4 subsequent siblings)
51 siblings, 0 replies; 53+ messages in thread
From: Christian Borntraeger @ 2016-06-21 13:13 UTC (permalink / raw)
To: Paolo Bonzini, Radim Krčmář
Cc: KVM, Cornelia Huck, linux-s390, Christian Borntraeger,
David Hildenbrand, Martin Schwidefsky
From: David Hildenbrand <dahi@linux.vnet.ibm.com>
As we want to make use of CPUSTAT_WAIT also when a VCPU is not idle but
to force interception of external calls, let's check in the bitmap instead.
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
arch/s390/kvm/kvm-s390.h | 2 +-
arch/s390/kvm/sigp.c | 10 +++++-----
2 files changed, 6 insertions(+), 6 deletions(-)
diff --git a/arch/s390/kvm/kvm-s390.h b/arch/s390/kvm/kvm-s390.h
index ffbbdd28..031f451 100644
--- a/arch/s390/kvm/kvm-s390.h
+++ b/arch/s390/kvm/kvm-s390.h
@@ -56,7 +56,7 @@ static inline int is_vcpu_stopped(struct kvm_vcpu *vcpu)
static inline int is_vcpu_idle(struct kvm_vcpu *vcpu)
{
- return atomic_read(&vcpu->arch.sie_block->cpuflags) & CPUSTAT_WAIT;
+ return test_bit(vcpu->vcpu_id, vcpu->arch.local_int.float_int->idle_mask);
}
static inline int kvm_is_ucontrol(struct kvm *kvm)
diff --git a/arch/s390/kvm/sigp.c b/arch/s390/kvm/sigp.c
index 28ea0ca..1a252f5 100644
--- a/arch/s390/kvm/sigp.c
+++ b/arch/s390/kvm/sigp.c
@@ -77,18 +77,18 @@ static int __sigp_conditional_emergency(struct kvm_vcpu *vcpu,
const u64 psw_int_mask = PSW_MASK_IO | PSW_MASK_EXT;
u16 p_asn, s_asn;
psw_t *psw;
- u32 flags;
+ bool idle;
- flags = atomic_read(&dst_vcpu->arch.sie_block->cpuflags);
+ idle = is_vcpu_idle(vcpu);
psw = &dst_vcpu->arch.sie_block->gpsw;
p_asn = dst_vcpu->arch.sie_block->gcr[4] & 0xffff; /* Primary ASN */
s_asn = dst_vcpu->arch.sie_block->gcr[3] & 0xffff; /* Secondary ASN */
/* Inject the emergency signal? */
- if (!(flags & CPUSTAT_STOPPED)
+ if (!is_vcpu_stopped(vcpu)
|| (psw->mask & psw_int_mask) != psw_int_mask
- || ((flags & CPUSTAT_WAIT) && psw->addr != 0)
- || (!(flags & CPUSTAT_WAIT) && (asn == p_asn || asn == s_asn))) {
+ || (idle && psw->addr != 0)
+ || (!idle && (asn == p_asn || asn == s_asn))) {
return __inject_sigp_emergency(vcpu, dst_vcpu);
} else {
*reg &= 0xffffffff00000000UL;
--
2.5.5
^ permalink raw reply related [flat|nested] 53+ messages in thread* [GIT PULL 48/51] KVM: s390: vsie: speed up VCPU external calls
2016-06-21 13:12 [GIT PULL 00/51] KVM: s390: vSIE (nested virtualization) feature for 4.8 (kvm/next) Christian Borntraeger
` (46 preceding siblings ...)
2016-06-21 13:13 ` [GIT PULL 47/51] KVM: s390: don't use CPUSTAT_WAIT to detect if a VCPU is idle Christian Borntraeger
@ 2016-06-21 13:13 ` Christian Borntraeger
2016-06-21 13:13 ` [GIT PULL 49/51] KVM: s390: vsie: correctly set and handle guest TOD Christian Borntraeger
` (3 subsequent siblings)
51 siblings, 0 replies; 53+ messages in thread
From: Christian Borntraeger @ 2016-06-21 13:13 UTC (permalink / raw)
To: Paolo Bonzini, Radim Krčmář
Cc: KVM, Cornelia Huck, linux-s390, Christian Borntraeger,
David Hildenbrand, Martin Schwidefsky
From: David Hildenbrand <dahi@linux.vnet.ibm.com>
Whenever a SIGP external call is injected via the SIGP external call
interpretation facility, the VCPU is not kicked. When a VCPU is currently
in the VSIE, the external call might not be processed immediately.
Therefore we have to provoke partial execution exceptions, which leads to a
kick of the VCPU and therefore also kick out of VSIE. This is done by
simulating the WAIT state. This bit has no other side effects.
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
arch/s390/kvm/vsie.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/arch/s390/kvm/vsie.c b/arch/s390/kvm/vsie.c
index c8c8763..90781ba 100644
--- a/arch/s390/kvm/vsie.c
+++ b/arch/s390/kvm/vsie.c
@@ -844,6 +844,11 @@ static void register_shadow_scb(struct kvm_vcpu *vcpu,
struct vsie_page *vsie_page)
{
WRITE_ONCE(vcpu->arch.vsie_block, &vsie_page->scb_s);
+ /*
+ * External calls have to lead to a kick of the vcpu and
+ * therefore the vsie -> Simulate Wait state.
+ */
+ atomic_or(CPUSTAT_WAIT, &vcpu->arch.sie_block->cpuflags);
}
/*
@@ -851,6 +856,7 @@ static void register_shadow_scb(struct kvm_vcpu *vcpu,
*/
static void unregister_shadow_scb(struct kvm_vcpu *vcpu)
{
+ atomic_andnot(CPUSTAT_WAIT, &vcpu->arch.sie_block->cpuflags);
WRITE_ONCE(vcpu->arch.vsie_block, NULL);
}
--
2.5.5
^ permalink raw reply related [flat|nested] 53+ messages in thread* [GIT PULL 49/51] KVM: s390: vsie: correctly set and handle guest TOD
2016-06-21 13:12 [GIT PULL 00/51] KVM: s390: vSIE (nested virtualization) feature for 4.8 (kvm/next) Christian Borntraeger
` (47 preceding siblings ...)
2016-06-21 13:13 ` [GIT PULL 48/51] KVM: s390: vsie: speed up VCPU external calls Christian Borntraeger
@ 2016-06-21 13:13 ` Christian Borntraeger
2016-06-21 13:13 ` [GIT PULL 50/51] KVM: s390: vsie: add indication for future features Christian Borntraeger
` (2 subsequent siblings)
51 siblings, 0 replies; 53+ messages in thread
From: Christian Borntraeger @ 2016-06-21 13:13 UTC (permalink / raw)
To: Paolo Bonzini, Radim Krčmář
Cc: KVM, Cornelia Huck, linux-s390, Christian Borntraeger,
David Hildenbrand, Martin Schwidefsky
From: David Hildenbrand <dahi@linux.vnet.ibm.com>
Guest 2 sets up the epoch of guest 3 from his point of view. Therefore,
we have to add the guest 2 epoch to the guest 3 epoch. We also have to take
care of guest 2 epoch changes on STP syncs. This will work just fine by
also updating the guest 3 epoch when a vsie_block has been set for a VCPU.
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
arch/s390/kvm/kvm-s390.c | 2 ++
arch/s390/kvm/vsie.c | 9 +++++++++
2 files changed, 11 insertions(+)
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 8ba7a98..6fdf1f7 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -176,6 +176,8 @@ static int kvm_clock_sync(struct notifier_block *notifier, unsigned long val,
vcpu->arch.sie_block->epoch -= *delta;
if (vcpu->arch.cputm_enabled)
vcpu->arch.cputm_start += *delta;
+ if (vcpu->arch.vsie_block)
+ vcpu->arch.vsie_block->epoch -= *delta;
}
}
return NOTIFY_OK;
diff --git a/arch/s390/kvm/vsie.c b/arch/s390/kvm/vsie.c
index 90781ba..6895e7b 100644
--- a/arch/s390/kvm/vsie.c
+++ b/arch/s390/kvm/vsie.c
@@ -843,12 +843,21 @@ static int acquire_gmap_shadow(struct kvm_vcpu *vcpu,
static void register_shadow_scb(struct kvm_vcpu *vcpu,
struct vsie_page *vsie_page)
{
+ struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s;
+
WRITE_ONCE(vcpu->arch.vsie_block, &vsie_page->scb_s);
/*
* External calls have to lead to a kick of the vcpu and
* therefore the vsie -> Simulate Wait state.
*/
atomic_or(CPUSTAT_WAIT, &vcpu->arch.sie_block->cpuflags);
+ /*
+ * We have to adjust the g3 epoch by the g2 epoch. The epoch will
+ * automatically be adjusted on tod clock changes via kvm_sync_clock.
+ */
+ preempt_disable();
+ scb_s->epoch += vcpu->kvm->arch.epoch;
+ preempt_enable();
}
/*
--
2.5.5
^ permalink raw reply related [flat|nested] 53+ messages in thread* [GIT PULL 50/51] KVM: s390: vsie: add indication for future features
2016-06-21 13:12 [GIT PULL 00/51] KVM: s390: vSIE (nested virtualization) feature for 4.8 (kvm/next) Christian Borntraeger
` (48 preceding siblings ...)
2016-06-21 13:13 ` [GIT PULL 49/51] KVM: s390: vsie: correctly set and handle guest TOD Christian Borntraeger
@ 2016-06-21 13:13 ` Christian Borntraeger
2016-06-21 13:13 ` [GIT PULL 51/51] KVM: s390: vsie: add module parameter "nested" Christian Borntraeger
2016-06-21 13:22 ` [GIT PULL 00/51] KVM: s390: vSIE (nested virtualization) feature for 4.8 (kvm/next) Paolo Bonzini
51 siblings, 0 replies; 53+ messages in thread
From: Christian Borntraeger @ 2016-06-21 13:13 UTC (permalink / raw)
To: Paolo Bonzini, Radim Krčmář
Cc: KVM, Cornelia Huck, linux-s390, Christian Borntraeger,
David Hildenbrand, Martin Schwidefsky
From: David Hildenbrand <dahi@linux.vnet.ibm.com>
We have certain SIE features that we cannot support for now.
Let's add these features, so user space can directly prepare to enable
them, so we don't have to update yet another component.
In addition, add a comment block, telling why it is for now not possible to
forward/enable these features.
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
arch/s390/include/uapi/asm/kvm.h | 4 ++++
arch/s390/kvm/kvm-s390.c | 18 ++++++++++++++++++
2 files changed, 22 insertions(+)
diff --git a/arch/s390/include/uapi/asm/kvm.h b/arch/s390/include/uapi/asm/kvm.h
index c128567..a2ffec4 100644
--- a/arch/s390/include/uapi/asm/kvm.h
+++ b/arch/s390/include/uapi/asm/kvm.h
@@ -106,6 +106,10 @@ struct kvm_s390_vm_cpu_machine {
#define KVM_S390_VM_CPU_FEAT_IB 6
#define KVM_S390_VM_CPU_FEAT_CEI 7
#define KVM_S390_VM_CPU_FEAT_IBS 8
+#define KVM_S390_VM_CPU_FEAT_SKEY 9
+#define KVM_S390_VM_CPU_FEAT_CMMA 10
+#define KVM_S390_VM_CPU_FEAT_PFMFI 11
+#define KVM_S390_VM_CPU_FEAT_SIGPIF 12
struct kvm_s390_vm_cpu_feat {
__u64 feat[16];
};
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 6fdf1f7..31cf22f 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -281,6 +281,24 @@ static void kvm_s390_cpu_feat_init(void)
allow_cpu_feat(KVM_S390_VM_CPU_FEAT_CEI);
if (sclp.has_ibs)
allow_cpu_feat(KVM_S390_VM_CPU_FEAT_IBS);
+ /*
+ * KVM_S390_VM_CPU_FEAT_SKEY: Wrong shadow of PTE.I bits will make
+ * all skey handling functions read/set the skey from the PGSTE
+ * instead of the real storage key.
+ *
+ * KVM_S390_VM_CPU_FEAT_CMMA: Wrong shadow of PTE.I bits will make
+ * pages being detected as preserved although they are resident.
+ *
+ * KVM_S390_VM_CPU_FEAT_PFMFI: Wrong shadow of PTE.I bits will
+ * have the same effect as for KVM_S390_VM_CPU_FEAT_SKEY.
+ *
+ * For KVM_S390_VM_CPU_FEAT_SKEY, KVM_S390_VM_CPU_FEAT_CMMA and
+ * KVM_S390_VM_CPU_FEAT_PFMFI, all PTE.I and PGSTE bits have to be
+ * correctly shadowed. We can do that for the PGSTE but not for PTE.I.
+ *
+ * KVM_S390_VM_CPU_FEAT_SIGPIF: Wrong SCB addresses in the SCA. We
+ * cannot easily shadow the SCA because of the ipte lock.
+ */
}
int kvm_arch_init(void *opaque)
--
2.5.5
^ permalink raw reply related [flat|nested] 53+ messages in thread* [GIT PULL 51/51] KVM: s390: vsie: add module parameter "nested"
2016-06-21 13:12 [GIT PULL 00/51] KVM: s390: vSIE (nested virtualization) feature for 4.8 (kvm/next) Christian Borntraeger
` (49 preceding siblings ...)
2016-06-21 13:13 ` [GIT PULL 50/51] KVM: s390: vsie: add indication for future features Christian Borntraeger
@ 2016-06-21 13:13 ` Christian Borntraeger
2016-06-21 13:22 ` [GIT PULL 00/51] KVM: s390: vSIE (nested virtualization) feature for 4.8 (kvm/next) Paolo Bonzini
51 siblings, 0 replies; 53+ messages in thread
From: Christian Borntraeger @ 2016-06-21 13:13 UTC (permalink / raw)
To: Paolo Bonzini, Radim Krčmář
Cc: KVM, Cornelia Huck, linux-s390, Christian Borntraeger,
David Hildenbrand, Martin Schwidefsky
From: David Hildenbrand <dahi@linux.vnet.ibm.com>
Let's be careful first and allow nested virtualization only if enabled
by the system administrator. In addition, user space still has to
explicitly enable it via SCLP features for it to work.
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
arch/s390/kvm/kvm-s390.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 31cf22f..03eeeb0 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -125,6 +125,11 @@ struct kvm_stats_debugfs_item debugfs_entries[] = {
{ NULL }
};
+/* allow nested virtualization in KVM (if enabled by user space) */
+static int nested;
+module_param(nested, int, S_IRUGO);
+MODULE_PARM_DESC(nested, "Nested virtualization support");
+
/* upper facilities limit for kvm */
unsigned long kvm_s390_fac_list_mask[16] = {
0xffe6000000000000UL,
@@ -264,7 +269,7 @@ static void kvm_s390_cpu_feat_init(void)
* 64bit SCAO (SCA passthrough) and IDTE (for gmap_shadow unshadowing).
*/
if (!sclp.has_sief2 || !MACHINE_HAS_ESOP || !sclp.has_64bscao ||
- !test_facility(3))
+ !test_facility(3) || !nested)
return;
allow_cpu_feat(KVM_S390_VM_CPU_FEAT_SIEF2);
if (sclp.has_64bscao)
--
2.5.5
^ permalink raw reply related [flat|nested] 53+ messages in thread* Re: [GIT PULL 00/51] KVM: s390: vSIE (nested virtualization) feature for 4.8 (kvm/next)
2016-06-21 13:12 [GIT PULL 00/51] KVM: s390: vSIE (nested virtualization) feature for 4.8 (kvm/next) Christian Borntraeger
` (50 preceding siblings ...)
2016-06-21 13:13 ` [GIT PULL 51/51] KVM: s390: vsie: add module parameter "nested" Christian Borntraeger
@ 2016-06-21 13:22 ` Paolo Bonzini
51 siblings, 0 replies; 53+ messages in thread
From: Paolo Bonzini @ 2016-06-21 13:22 UTC (permalink / raw)
To: Christian Borntraeger, Radim Krčmář
Cc: KVM, Cornelia Huck, linux-s390, David Hildenbrand, Martin Schwidefsky
On 21/06/2016 15:12, Christian Borntraeger wrote:
> git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux.git tags/kvm-s390-next-4.8-2
Pulled, thanks!
Paolo
^ permalink raw reply [flat|nested] 53+ messages in thread